diff --git a/cmd/thanos/main_test.go b/cmd/thanos/main_test.go
index a9930139959..3bcc94a3ab3 100644
--- a/cmd/thanos/main_test.go
+++ b/cmd/thanos/main_test.go
@@ -22,7 +22,7 @@ import (
 	"github.com/thanos-io/thanos/pkg/block/metadata"
 	"github.com/thanos-io/thanos/pkg/compact"
 	"github.com/thanos-io/thanos/pkg/compact/downsample"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
+	"github.com/thanos-io/thanos/pkg/objstore"
 	"github.com/thanos-io/thanos/pkg/testutil"
 	"github.com/thanos-io/thanos/pkg/testutil/e2eutil"
 )
@@ -36,7 +36,7 @@ func TestCleanupIndexCacheFolder(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
 	defer cancel()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NoopInstrumentedBucket{objstore.NewInMemBucket()}
 
 	// Upload one compaction lvl = 2 block, one compaction lvl = 1.
 	// We generate index cache files only for lvl > 1 blocks.
@@ -97,7 +97,7 @@ func TestCleanupDownsampleCacheFolder(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
 	defer cancel()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NoopInstrumentedBucket{objstore.NewInMemBucket()}
 	var id ulid.ULID
 	{
 		id, err = e2eutil.CreateBlock(
diff --git a/pkg/block/block_test.go b/pkg/block/block_test.go
index 6e2193b5d7a..503d09db75d 100644
--- a/pkg/block/block_test.go
+++ b/pkg/block/block_test.go
@@ -19,7 +19,7 @@ import (
 	"github.com/go-kit/kit/log"
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/thanos-io/thanos/pkg/block/metadata"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
+	"github.com/thanos-io/thanos/pkg/objstore"
 	"github.com/thanos-io/thanos/pkg/testutil"
 	"github.com/thanos-io/thanos/pkg/testutil/e2eutil"
 
@@ -81,7 +81,7 @@ func TestUpload(t *testing.T) {
 	testutil.Ok(t, err)
 	defer func() { testutil.Ok(t, os.RemoveAll(tmpDir)) }()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NewInMemBucket()
 	b1, err := e2eutil.CreateBlock(ctx, tmpDir, []labels.Labels{
 		{{Name: "a", Value: "1"}},
 		{{Name: "a", Value: "2"}},
@@ -185,7 +185,7 @@ func TestDelete(t *testing.T) {
 	testutil.Ok(t, err)
 	defer func() { testutil.Ok(t, os.RemoveAll(tmpDir)) }()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NewInMemBucket()
 	{
 		b1, err := e2eutil.CreateBlock(ctx, tmpDir, []labels.Labels{
 			{{Name: "a", Value: "1"}},
@@ -232,7 +232,7 @@ func TestMarkForDeletion(t *testing.T) {
 	testutil.Ok(t, err)
 	defer func() { testutil.Ok(t, os.RemoveAll(tmpDir)) }()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NewInMemBucket()
 	{
 		blockWithoutDeletionMark, err := e2eutil.CreateBlock(ctx, tmpDir, []labels.Labels{
 			{{Name: "a", Value: "1"}},
diff --git a/pkg/block/fetcher.go b/pkg/block/fetcher.go
index e83bc5633dd..0a8ca111966 100644
--- a/pkg/block/fetcher.go
+++ b/pkg/block/fetcher.go
@@ -142,7 +142,7 @@ type MetadataModifier interface {
 type BaseFetcher struct {
 	logger      log.Logger
 	concurrency int
-	bkt         objstore.BucketReader
+	bkt         objstore.InstrumentedBucketReader
 
 	// Optional local directory to cache meta.json files.
 	cacheDir string
@@ -152,7 +152,7 @@ type BaseFetcher struct {
 }
 
 // NewBaseFetcher constructs BaseFetcher.
-func NewBaseFetcher(logger log.Logger, concurrency int, bkt objstore.BucketReader, dir string, reg prometheus.Registerer) (*BaseFetcher, error) {
+func NewBaseFetcher(logger log.Logger, concurrency int, bkt objstore.InstrumentedBucketReader, dir string, reg prometheus.Registerer) (*BaseFetcher, error) {
 	if logger == nil {
 		logger = log.NewNopLogger()
 	}
@@ -180,7 +180,7 @@ func NewBaseFetcher(logger log.Logger, concurrency int, bkt objstore.BucketReade
 }
 
 // NewMetaFetcher returns meta fetcher.
-func NewMetaFetcher(logger log.Logger, concurrency int, bkt objstore.BucketReader, dir string, reg prometheus.Registerer, filters []MetadataFilter, modifiers []MetadataModifier) (*MetaFetcher, error) {
+func NewMetaFetcher(logger log.Logger, concurrency int, bkt objstore.InstrumentedBucketReader, dir string, reg prometheus.Registerer, filters []MetadataFilter, modifiers []MetadataModifier) (*MetaFetcher, error) {
 	b, err := NewBaseFetcher(logger, concurrency, bkt, dir, reg)
 	if err != nil {
 		return nil, err
@@ -236,7 +236,7 @@ func (f *BaseFetcher) loadMeta(ctx context.Context, id ulid.ULID) (*metadata.Met
 		}
 	}
 
-	r, err := f.bkt.Get(ctx, metaFile)
+	r, err := f.bkt.ReaderWithExpectedErrs(f.bkt.IsObjNotFoundErr).Get(ctx, metaFile)
 	if f.bkt.IsObjNotFoundErr(err) {
 		// Meta.json was deleted between bkt.Exists and here.
 		return nil, errors.Wrapf(ErrorSyncMetaNotFound, "%v", err)
@@ -740,12 +740,12 @@ func (f *ConsistencyDelayMetaFilter) Filter(_ context.Context, metas map[ulid.UL
 type IgnoreDeletionMarkFilter struct {
 	logger          log.Logger
 	delay           time.Duration
-	bkt             objstore.BucketReader
+	bkt             objstore.InstrumentedBucketReader
 	deletionMarkMap map[ulid.ULID]*metadata.DeletionMark
 }
 
 // NewIgnoreDeletionMarkFilter creates IgnoreDeletionMarkFilter.
-func NewIgnoreDeletionMarkFilter(logger log.Logger, bkt objstore.BucketReader, delay time.Duration) *IgnoreDeletionMarkFilter {
+func NewIgnoreDeletionMarkFilter(logger log.Logger, bkt objstore.InstrumentedBucketReader, delay time.Duration) *IgnoreDeletionMarkFilter {
 	return &IgnoreDeletionMarkFilter{
 		logger: logger,
 		bkt:    bkt,
diff --git a/pkg/block/fetcher_test.go b/pkg/block/fetcher_test.go
index 953ed93f4fe..23ba8b3b16c 100644
--- a/pkg/block/fetcher_test.go
+++ b/pkg/block/fetcher_test.go
@@ -75,7 +75,7 @@ func TestMetaFetcher_Fetch(t *testing.T) {
 
 		var ulidToDelete ulid.ULID
 		r := prometheus.NewRegistry()
-		baseFetcher, err := NewBaseFetcher(log.NewNopLogger(), 20, bkt, dir, r)
+		baseFetcher, err := NewBaseFetcher(log.NewNopLogger(), 20, objstore.NoopInstrumentedBucket{bkt}, dir, r)
 		testutil.Ok(t, err)
 
 		fetcher := baseFetcher.NewMetaFetcher(r, []MetadataFilter{
@@ -1065,7 +1065,7 @@ func TestIgnoreDeletionMarkFilter_Filter(t *testing.T) {
 		now := time.Now()
 		f := &IgnoreDeletionMarkFilter{
 			logger: log.NewNopLogger(),
-			bkt:    bkt,
+			bkt:    objstore.NoopInstrumentedBucket{bkt},
 			delay:  48 * time.Hour,
 		}
 
diff --git a/pkg/block/indexheader/json_reader.go b/pkg/block/indexheader/json_reader.go
index 5a3654f4d60..fe54534972f 100644
--- a/pkg/block/indexheader/json_reader.go
+++ b/pkg/block/indexheader/json_reader.go
@@ -199,7 +199,7 @@ type JSONReader struct {
 }
 
 // NewJSONReader loads or builds new index-cache.json if not present on disk or object storage.
-func NewJSONReader(ctx context.Context, logger log.Logger, bkt objstore.BucketReader, dir string, id ulid.ULID) (*JSONReader, error) {
+func NewJSONReader(ctx context.Context, logger log.Logger, bkt objstore.InstrumentedBucketReader, dir string, id ulid.ULID) (*JSONReader, error) {
 	cachefn := filepath.Join(dir, id.String(), block.IndexCacheFilename)
 	jr, err := newFileJSONReader(logger, cachefn)
 	if err == nil {
@@ -216,7 +216,7 @@ func NewJSONReader(ctx context.Context, logger log.Logger, bkt objstore.BucketRe
 	}
 
 	// Try to download index cache file from object store.
-	if err = objstore.DownloadFile(ctx, logger, bkt, filepath.Join(id.String(), block.IndexCacheFilename), cachefn); err == nil {
+	if err = objstore.DownloadFile(ctx, logger, bkt.ReaderWithExpectedErrs(bkt.IsObjNotFoundErr), filepath.Join(id.String(), block.IndexCacheFilename), cachefn); err == nil {
 		return newFileJSONReader(logger, cachefn)
 	}
 
diff --git a/pkg/block/metadata/deletionmark.go b/pkg/block/metadata/deletionmark.go
index bda97e92c6c..5f2a9f04adc 100644
--- a/pkg/block/metadata/deletionmark.go
+++ b/pkg/block/metadata/deletionmark.go
@@ -45,10 +45,10 @@ type DeletionMark struct {
 }
 
 // ReadDeletionMark reads the given deletion mark file from <dir>/deletion-mark.json in bucket.
-func ReadDeletionMark(ctx context.Context, bkt objstore.BucketReader, logger log.Logger, dir string) (*DeletionMark, error) {
+func ReadDeletionMark(ctx context.Context, bkt objstore.InstrumentedBucketReader, logger log.Logger, dir string) (*DeletionMark, error) {
 	deletionMarkFile := path.Join(dir, DeletionMarkFilename)
 
-	r, err := bkt.Get(ctx, deletionMarkFile)
+	r, err := bkt.ReaderWithExpectedErrs(bkt.IsObjNotFoundErr).Get(ctx, deletionMarkFile)
 	if err != nil {
 		if bkt.IsObjNotFoundErr(err) {
 			return nil, ErrorDeletionMarkNotFound
diff --git a/pkg/block/metadata/deletionmark_test.go b/pkg/block/metadata/deletionmark_test.go
index 73f632e9af4..4afcfd945af 100644
--- a/pkg/block/metadata/deletionmark_test.go
+++ b/pkg/block/metadata/deletionmark_test.go
@@ -16,7 +16,7 @@ import (
 	"github.com/fortytw2/leaktest"
 	"github.com/oklog/ulid"
 	"github.com/pkg/errors"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
+	"github.com/thanos-io/thanos/pkg/objstore"
 	"github.com/thanos-io/thanos/pkg/testutil"
 )
 
@@ -29,7 +29,7 @@ func TestReadDeletionMark(t *testing.T) {
 	testutil.Ok(t, err)
 	defer func() { testutil.Ok(t, os.RemoveAll(tmpDir)) }()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NoopInstrumentedBucket{objstore.NewInMemBucket()}
 	{
 		blockWithoutDeletionMark := ulid.MustNew(uint64(1), nil)
 		_, err := ReadDeletionMark(ctx, bkt, nil, path.Join(tmpDir, blockWithoutDeletionMark.String()))
diff --git a/pkg/compact/clean_test.go b/pkg/compact/clean_test.go
index 9a7889ead8e..cd05988e1e8 100644
--- a/pkg/compact/clean_test.go
+++ b/pkg/compact/clean_test.go
@@ -18,7 +18,7 @@ import (
 	promtest "github.com/prometheus/client_golang/prometheus/testutil"
 	"github.com/thanos-io/thanos/pkg/block"
 	"github.com/thanos-io/thanos/pkg/block/metadata"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
+	"github.com/thanos-io/thanos/pkg/objstore"
 	"github.com/thanos-io/thanos/pkg/testutil"
 )
 
@@ -26,7 +26,7 @@ func TestBestEffortCleanAbortedPartialUploads(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
 	defer cancel()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NoopInstrumentedBucket{objstore.NewInMemBucket()}
 	logger := log.NewNopLogger()
 
 	metaFetcher, err := block.NewMetaFetcher(nil, 32, bkt, "", nil, nil, nil)
diff --git a/pkg/compact/compact_e2e_test.go b/pkg/compact/compact_e2e_test.go
index 21de5cfca76..3f98faea72e 100644
--- a/pkg/compact/compact_e2e_test.go
+++ b/pkg/compact/compact_e2e_test.go
@@ -90,7 +90,7 @@ func TestSyncer_GarbageCollect_e2e(t *testing.T) {
 		}
 
 		duplicateBlocksFilter := block.NewDeduplicateFilter()
-		metaFetcher, err := block.NewMetaFetcher(nil, 32, bkt, "", nil, []block.MetadataFilter{
+		metaFetcher, err := block.NewMetaFetcher(nil, 32, objstore.NoopInstrumentedBucket{bkt}, "", nil, []block.MetadataFilter{
 			duplicateBlocksFilter,
 		}, nil)
 		testutil.Ok(t, err)
@@ -176,9 +176,9 @@ func TestGroup_Compact_e2e(t *testing.T) {
 
 		reg := prometheus.NewRegistry()
 
-		ignoreDeletionMarkFilter := block.NewIgnoreDeletionMarkFilter(logger, bkt, 48*time.Hour)
+		ignoreDeletionMarkFilter := block.NewIgnoreDeletionMarkFilter(logger, objstore.NoopInstrumentedBucket{bkt}, 48*time.Hour)
 		duplicateBlocksFilter := block.NewDeduplicateFilter()
-		metaFetcher, err := block.NewMetaFetcher(nil, 32, bkt, "", nil, []block.MetadataFilter{
+		metaFetcher, err := block.NewMetaFetcher(nil, 32, objstore.NoopInstrumentedBucket{bkt}, "", nil, []block.MetadataFilter{
 			ignoreDeletionMarkFilter,
 			duplicateBlocksFilter,
 		}, nil)
diff --git a/pkg/compact/retention_test.go b/pkg/compact/retention_test.go
index 0a1431996e8..4aeaeea6746 100644
--- a/pkg/compact/retention_test.go
+++ b/pkg/compact/retention_test.go
@@ -22,7 +22,6 @@ import (
 	"github.com/thanos-io/thanos/pkg/block/metadata"
 	"github.com/thanos-io/thanos/pkg/compact"
 	"github.com/thanos-io/thanos/pkg/objstore"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
 	"github.com/thanos-io/thanos/pkg/testutil"
 )
 
@@ -240,7 +239,7 @@ func TestApplyRetentionPolicyByResolution(t *testing.T) {
 		},
 	} {
 		t.Run(tt.name, func(t *testing.T) {
-			bkt := inmem.NewBucket()
+			bkt := objstore.NoopInstrumentedBucket{objstore.NewInMemBucket()}
 			for _, b := range tt.blocks {
 				uploadMockBlock(t, bkt, b.id, b.minTime, b.maxTime, int64(b.resolution))
 			}
diff --git a/pkg/objstore/azure/azure.go b/pkg/objstore/azure/azure.go
index 0c132daf61b..97603abdf18 100644
--- a/pkg/objstore/azure/azure.go
+++ b/pkg/objstore/azure/azure.go
@@ -64,7 +64,7 @@ func (conf *Config) validate() error {
 	return nil
 }
 
-// NewBucket returns a new Bucket using the provided Azure config.
+// NewInMemBucket returns a new Bucket using the provided Azure config.
 func NewBucket(logger log.Logger, azureConfig []byte, component string) (*Bucket, error) {
 	level.Debug(logger).Log("msg", "creating new Azure bucket connection", "component", component)
 
diff --git a/pkg/objstore/client/factory.go b/pkg/objstore/client/factory.go
index 6caf7f8ee43..687cf61ec46 100644
--- a/pkg/objstore/client/factory.go
+++ b/pkg/objstore/client/factory.go
@@ -40,9 +40,9 @@ type BucketConfig struct {
 	Config interface{} `yaml:"config"`
 }
 
-// NewBucket initializes and returns new object storage clients.
+// NewInMemBucket initializes and returns new object storage clients.
 // NOTE: confContentYaml can contain secrets.
-func NewBucket(logger log.Logger, confContentYaml []byte, reg prometheus.Registerer, component string) (objstore.Bucket, error) {
+func NewBucket(logger log.Logger, confContentYaml []byte, reg prometheus.Registerer, component string) (objstore.InstrumentedBucket, error) {
 	level.Info(logger).Log("msg", "loading bucket configuration")
 	bucketConf := &BucketConfig{}
 	if err := yaml.UnmarshalStrict(confContentYaml, bucketConf); err != nil {
diff --git a/pkg/objstore/filesystem/filesystem.go b/pkg/objstore/filesystem/filesystem.go
index 0a13994d938..6965ee64494 100644
--- a/pkg/objstore/filesystem/filesystem.go
+++ b/pkg/objstore/filesystem/filesystem.go
@@ -43,7 +43,7 @@ func NewBucketFromConfig(conf []byte) (*Bucket, error) {
 	return NewBucket(c.Directory)
 }
 
-// NewBucket returns a new filesystem.Bucket.
+// NewInMemBucket returns a new filesystem.Bucket.
 func NewBucket(rootDir string) (*Bucket, error) {
 	absDir, err := filepath.Abs(rootDir)
 	if err != nil {
diff --git a/pkg/objstore/gcs/gcs.go b/pkg/objstore/gcs/gcs.go
index ae2cf3202bb..e23a59077c5 100644
--- a/pkg/objstore/gcs/gcs.go
+++ b/pkg/objstore/gcs/gcs.go
@@ -41,7 +41,7 @@ type Bucket struct {
 	closer io.Closer
 }
 
-// NewBucket returns a new Bucket against the given bucket handle.
+// NewInMemBucket returns a new Bucket against the given bucket handle.
 func NewBucket(ctx context.Context, logger log.Logger, conf []byte, component string) (*Bucket, error) {
 	var gc Config
 	if err := yaml.Unmarshal(conf, &gc); err != nil {
diff --git a/pkg/objstore/inmem/inmem.go b/pkg/objstore/inmem.go
similarity index 72%
rename from pkg/objstore/inmem/inmem.go
rename to pkg/objstore/inmem.go
index 7f430c3c97b..68f1c1cd199 100644
--- a/pkg/objstore/inmem/inmem.go
+++ b/pkg/objstore/inmem.go
@@ -1,7 +1,7 @@
 // Copyright (c) The Thanos Authors.
 // Licensed under the Apache License 2.0.
 
-package inmem
+package objstore
 
 import (
 	"bytes"
@@ -13,37 +13,36 @@ import (
 	"sync"
 
 	"github.com/pkg/errors"
-	"github.com/thanos-io/thanos/pkg/objstore"
 )
 
 var errNotFound = errors.New("inmem: object not found")
 
 // Bucket implements the objstore.Bucket interfaces against local memory.
 // Methods from Bucket interface are thread-safe. Objects are assumed to be immutable.
-type Bucket struct {
+type InMemBucket struct {
 	mtx     sync.RWMutex
 	objects map[string][]byte
 }
 
-// NewBucket returns a new in memory Bucket.
+// NewInMemBucket returns a new in memory Bucket.
 // NOTE: Returned bucket is just a naive in memory bucket implementation. For test use cases only.
-func NewBucket() *Bucket {
-	return &Bucket{objects: map[string][]byte{}}
+func NewInMemBucket() *InMemBucket {
+	return &InMemBucket{objects: map[string][]byte{}}
 }
 
 // Objects returns internally stored objects.
 // NOTE: For assert purposes.
-func (b *Bucket) Objects() map[string][]byte {
+func (b *InMemBucket) Objects() map[string][]byte {
 	return b.objects
 }
 
 // Iter calls f for each entry in the given directory. The argument to f is the full
 // object name including the prefix of the inspected directory.
-func (b *Bucket) Iter(_ context.Context, dir string, f func(string) error) error {
+func (b *InMemBucket) Iter(_ context.Context, dir string, f func(string) error) error {
 	unique := map[string]struct{}{}
 
 	var dirPartsCount int
-	dirParts := strings.SplitAfter(dir, objstore.DirDelim)
+	dirParts := strings.SplitAfter(dir, DirDelim)
 	for _, p := range dirParts {
 		if p == "" {
 			continue
@@ -57,7 +56,7 @@ func (b *Bucket) Iter(_ context.Context, dir string, f func(string) error) error
 			continue
 		}
 
-		parts := strings.SplitAfter(filename, objstore.DirDelim)
+		parts := strings.SplitAfter(filename, DirDelim)
 		unique[strings.Join(parts[:dirPartsCount+1], "")] = struct{}{}
 	}
 	b.mtx.RUnlock()
@@ -67,13 +66,13 @@ func (b *Bucket) Iter(_ context.Context, dir string, f func(string) error) error
 		keys = append(keys, n)
 	}
 	sort.Slice(keys, func(i, j int) bool {
-		if strings.HasSuffix(keys[i], objstore.DirDelim) && strings.HasSuffix(keys[j], objstore.DirDelim) {
+		if strings.HasSuffix(keys[i], DirDelim) && strings.HasSuffix(keys[j], DirDelim) {
 			return strings.Compare(keys[i], keys[j]) < 0
 		}
-		if strings.HasSuffix(keys[i], objstore.DirDelim) {
+		if strings.HasSuffix(keys[i], DirDelim) {
 			return false
 		}
-		if strings.HasSuffix(keys[j], objstore.DirDelim) {
+		if strings.HasSuffix(keys[j], DirDelim) {
 			return true
 		}
 
@@ -89,7 +88,7 @@ func (b *Bucket) Iter(_ context.Context, dir string, f func(string) error) error
 }
 
 // Get returns a reader for the given object name.
-func (b *Bucket) Get(_ context.Context, name string) (io.ReadCloser, error) {
+func (b *InMemBucket) Get(_ context.Context, name string) (io.ReadCloser, error) {
 	if name == "" {
 		return nil, errors.New("inmem: object name is empty")
 	}
@@ -105,7 +104,7 @@ func (b *Bucket) Get(_ context.Context, name string) (io.ReadCloser, error) {
 }
 
 // GetRange returns a new range reader for the given object name and range.
-func (b *Bucket) GetRange(_ context.Context, name string, off, length int64) (io.ReadCloser, error) {
+func (b *InMemBucket) GetRange(_ context.Context, name string, off, length int64) (io.ReadCloser, error) {
 	if name == "" {
 		return nil, errors.New("inmem: object name is empty")
 	}
@@ -138,7 +137,7 @@ func (b *Bucket) GetRange(_ context.Context, name string, off, length int64) (io
 }
 
 // Exists checks if the given directory exists in memory.
-func (b *Bucket) Exists(_ context.Context, name string) (bool, error) {
+func (b *InMemBucket) Exists(_ context.Context, name string) (bool, error) {
 	b.mtx.RLock()
 	defer b.mtx.RUnlock()
 	_, ok := b.objects[name]
@@ -146,7 +145,7 @@ func (b *Bucket) Exists(_ context.Context, name string) (bool, error) {
 }
 
 // ObjectSize returns the size of the specified object.
-func (b *Bucket) ObjectSize(_ context.Context, name string) (uint64, error) {
+func (b *InMemBucket) ObjectSize(_ context.Context, name string) (uint64, error) {
 	b.mtx.RLock()
 	file, ok := b.objects[name]
 	b.mtx.RUnlock()
@@ -157,7 +156,7 @@ func (b *Bucket) ObjectSize(_ context.Context, name string) (uint64, error) {
 }
 
 // Upload writes the file specified in src to into the memory.
-func (b *Bucket) Upload(_ context.Context, name string, r io.Reader) error {
+func (b *InMemBucket) Upload(_ context.Context, name string, r io.Reader) error {
 	b.mtx.Lock()
 	defer b.mtx.Unlock()
 	body, err := ioutil.ReadAll(r)
@@ -169,7 +168,7 @@ func (b *Bucket) Upload(_ context.Context, name string, r io.Reader) error {
 }
 
 // Delete removes all data prefixed with the dir.
-func (b *Bucket) Delete(_ context.Context, name string) error {
+func (b *InMemBucket) Delete(_ context.Context, name string) error {
 	b.mtx.Lock()
 	defer b.mtx.Unlock()
 	if _, ok := b.objects[name]; !ok {
@@ -180,13 +179,13 @@ func (b *Bucket) Delete(_ context.Context, name string) error {
 }
 
 // IsObjNotFoundErr returns true if error means that object is not found. Relevant to Get operations.
-func (b *Bucket) IsObjNotFoundErr(err error) bool {
-	return err == errNotFound
+func (b *InMemBucket) IsObjNotFoundErr(err error) bool {
+	return errors.Cause(err) == errNotFound
 }
 
-func (b *Bucket) Close() error { return nil }
+func (b *InMemBucket) Close() error { return nil }
 
 // Name returns the bucket name.
-func (b *Bucket) Name() string {
+func (b *InMemBucket) Name() string {
 	return "inmem"
 }
diff --git a/pkg/objstore/objstore.go b/pkg/objstore/objstore.go
index 23926054ad2..c1bb44d0792 100644
--- a/pkg/objstore/objstore.go
+++ b/pkg/objstore/objstore.go
@@ -6,13 +6,10 @@ package objstore
 import (
 	"bytes"
 	"context"
-	"fmt"
 	"io"
-	"math/rand"
 	"os"
 	"path/filepath"
 	"strings"
-	"testing"
 	"time"
 
 	"github.com/go-kit/kit/log"
@@ -41,22 +38,18 @@ type Bucket interface {
 	Name() string
 }
 
-// TryToGetSize tries to get upfront size from reader.
-// TODO(https://github.com/thanos-io/thanos/issues/678): Remove guessing length when minio provider will support multipart upload without this.
-func TryToGetSize(r io.Reader) (int64, error) {
-	switch f := r.(type) {
-	case *os.File:
-		fileInfo, err := f.Stat()
-		if err != nil {
-			return 0, errors.Wrap(err, "os.File.Stat()")
-		}
-		return fileInfo.Size(), nil
-	case *bytes.Buffer:
-		return int64(f.Len()), nil
-	case *strings.Reader:
-		return f.Size(), nil
-	}
-	return 0, errors.New("unsupported type of io.Reader")
+// InstrumentedBucket is a Bucket with optional instrumentation control on reader.
+type InstrumentedBucket interface {
+	Bucket
+
+	// WithExpectedErrs allows to specify a filter that marks certain errors as expected, so it will not increment
+	// thanos_objstore_bucket_operation_failures_total metric.
+	WithExpectedErrs(IsOpFailureExpectedFunc) Bucket
+
+	// ReaderWithExpectedErrs allows to specify a filter that marks certain errors as expected, so it will not increment
+	// thanos_objstore_bucket_operation_failures_total metric.
+	// TODO(bwplotka): Remove this when moved to Go 1.14 and replace with InstrumentedBucketReader.
+	ReaderWithExpectedErrs(IsOpFailureExpectedFunc) BucketReader
 }
 
 // BucketReader provides read access to an object storage bucket.
@@ -81,6 +74,33 @@ type BucketReader interface {
 	ObjectSize(ctx context.Context, name string) (uint64, error)
 }
 
+// InstrumentedBucket is a BucketReader with optional instrumentation control.
+type InstrumentedBucketReader interface {
+	BucketReader
+
+	// ReaderWithExpectedErrs allows to specify a filter that marks certain errors as expected, so it will not increment
+	// thanos_objstore_bucket_operation_failures_total metric.
+	ReaderWithExpectedErrs(IsOpFailureExpectedFunc) BucketReader
+}
+
+// TryToGetSize tries to get upfront size from reader.
+// TODO(https://github.com/thanos-io/thanos/issues/678): Remove guessing length when minio provider will support multipart upload without this.
+func TryToGetSize(r io.Reader) (int64, error) {
+	switch f := r.(type) {
+	case *os.File:
+		fileInfo, err := f.Stat()
+		if err != nil {
+			return 0, errors.Wrap(err, "os.File.Stat()")
+		}
+		return fileInfo.Size(), nil
+	case *bytes.Buffer:
+		return int64(f.Len()), nil
+	case *strings.Reader:
+		return f.Size(), nil
+	}
+	return 0, errors.New("unsupported type of io.Reader")
+}
+
 // UploadDir uploads all files in srcdir to the bucket with into a top-level directory
 // named dstdir. It is a caller responsibility to clean partial upload in case of failure.
 func UploadDir(ctx context.Context, logger log.Logger, bkt Bucket, srcdir, dstdir string) error {
@@ -200,27 +220,32 @@ const (
 	deleteOp   = "delete"
 )
 
+// IsOpFailureExpectedFunc allows to mark certain errors as expected, so they will not increment thanos_objstore_bucket_operation_failures_total metric.
+type IsOpFailureExpectedFunc func(error) bool
+
+var _ InstrumentedBucket = &metricBucket{}
+
 // BucketWithMetrics takes a bucket and registers metrics with the given registry for
 // operations run against the bucket.
-func BucketWithMetrics(name string, b Bucket, reg prometheus.Registerer) Bucket {
+func BucketWithMetrics(name string, b Bucket, reg prometheus.Registerer) *metricBucket {
 	bkt := &metricBucket{
-		bkt: b,
-
+		bkt:                 b,
+		isOpFailureExpected: func(err error) bool { return false },
 		ops: promauto.With(reg).NewCounterVec(prometheus.CounterOpts{
 			Name:        "thanos_objstore_bucket_operations_total",
-			Help:        "Total number of operations against a bucket.",
+			Help:        "Total number of all attempted operations against a bucket.",
 			ConstLabels: prometheus.Labels{"bucket": name},
 		}, []string{"operation"}),
 
 		opsFailures: promauto.With(reg).NewCounterVec(prometheus.CounterOpts{
 			Name:        "thanos_objstore_bucket_operation_failures_total",
-			Help:        "Total number of operations against a bucket that failed.",
+			Help:        "Total number of operations against a bucket that failed, but were not expected to fail in certain way from caller perspective. Those errors have to be investigated.",
 			ConstLabels: prometheus.Labels{"bucket": name},
 		}, []string{"operation"}),
 
 		opsDuration: promauto.With(reg).NewHistogramVec(prometheus.HistogramOpts{
 			Name:        "thanos_objstore_bucket_operation_duration_seconds",
-			Help:        "Duration of operations against the bucket",
+			Help:        "Duration of successful operations against the bucket",
 			ConstLabels: prometheus.Labels{"bucket": name},
 			Buckets:     []float64{0.001, 0.01, 0.1, 0.3, 0.6, 1, 3, 6, 9, 20, 30, 60, 90, 120},
 		}, []string{"operation"}),
@@ -229,7 +254,15 @@ func BucketWithMetrics(name string, b Bucket, reg prometheus.Registerer) Bucket
 			Help: "Second timestamp of the last successful upload to the bucket.",
 		}, []string{"bucket"}),
 	}
-	for _, op := range []string{iterOp, sizeOp, getOp, getRangeOp, existsOp, uploadOp, deleteOp} {
+	for _, op := range []string{
+		iterOp,
+		sizeOp,
+		getOp,
+		getRangeOp,
+		existsOp,
+		uploadOp,
+		deleteOp,
+	} {
 		bkt.ops.WithLabelValues(op)
 		bkt.opsFailures.WithLabelValues(op)
 		bkt.opsDuration.WithLabelValues(op)
@@ -241,107 +274,142 @@ func BucketWithMetrics(name string, b Bucket, reg prometheus.Registerer) Bucket
 type metricBucket struct {
 	bkt Bucket
 
-	ops                      *prometheus.CounterVec
-	opsFailures              *prometheus.CounterVec
+	ops                 *prometheus.CounterVec
+	opsFailures         *prometheus.CounterVec
+	isOpFailureExpected IsOpFailureExpectedFunc
+
 	opsDuration              *prometheus.HistogramVec
 	lastSuccessfulUploadTime *prometheus.GaugeVec
 }
 
+func (b *metricBucket) WithExpectedErrs(fn IsOpFailureExpectedFunc) Bucket {
+	return &metricBucket{
+		bkt:                      b.bkt,
+		ops:                      b.ops,
+		opsFailures:              b.opsFailures,
+		isOpFailureExpected:      fn,
+		opsDuration:              b.opsDuration,
+		lastSuccessfulUploadTime: b.lastSuccessfulUploadTime,
+	}
+}
+
+func (b *metricBucket) ReaderWithExpectedErrs(fn IsOpFailureExpectedFunc) BucketReader {
+	return b.WithExpectedErrs(fn)
+}
+
 func (b *metricBucket) Iter(ctx context.Context, dir string, f func(name string) error) error {
+	const op = iterOp
+	b.ops.WithLabelValues(op).Inc()
+
 	err := b.bkt.Iter(ctx, dir, f)
-	if err != nil {
-		b.opsFailures.WithLabelValues(iterOp).Inc()
+	if err != nil && !b.isOpFailureExpected(err) {
+		b.opsFailures.WithLabelValues(op).Inc()
 	}
-	b.ops.WithLabelValues(iterOp).Inc()
-
 	return err
 }
 
-// ObjectSize returns the size of the specified object.
 func (b *metricBucket) ObjectSize(ctx context.Context, name string) (uint64, error) {
-	b.ops.WithLabelValues(sizeOp).Inc()
-	start := time.Now()
+	const op = sizeOp
+	b.ops.WithLabelValues(op).Inc()
 
+	start := time.Now()
 	rc, err := b.bkt.ObjectSize(ctx, name)
 	if err != nil {
-		b.opsFailures.WithLabelValues(sizeOp).Inc()
+		if !b.isOpFailureExpected(err) {
+			b.opsFailures.WithLabelValues(op).Inc()
+		}
 		return 0, err
 	}
-	b.opsDuration.WithLabelValues(sizeOp).Observe(time.Since(start).Seconds())
+	b.opsDuration.WithLabelValues(op).Observe(time.Since(start).Seconds())
 	return rc, nil
 }
 
 func (b *metricBucket) Get(ctx context.Context, name string) (io.ReadCloser, error) {
-	b.ops.WithLabelValues(getOp).Inc()
+	const op = getOp
+	b.ops.WithLabelValues(op).Inc()
 
 	rc, err := b.bkt.Get(ctx, name)
 	if err != nil {
-		b.opsFailures.WithLabelValues(getOp).Inc()
+		if !b.isOpFailureExpected(err) {
+			b.opsFailures.WithLabelValues(op).Inc()
+		}
 		return nil, err
 	}
 	return newTimingReadCloser(
 		rc,
-		getOp,
+		op,
 		b.opsDuration,
 		b.opsFailures,
+		b.isOpFailureExpected,
 	), nil
 }
 
 func (b *metricBucket) GetRange(ctx context.Context, name string, off, length int64) (io.ReadCloser, error) {
-	b.ops.WithLabelValues(getRangeOp).Inc()
+	const op = getRangeOp
+	b.ops.WithLabelValues(op).Inc()
 
 	rc, err := b.bkt.GetRange(ctx, name, off, length)
 	if err != nil {
-		b.opsFailures.WithLabelValues(getRangeOp).Inc()
+		if !b.isOpFailureExpected(err) {
+			b.opsFailures.WithLabelValues(op).Inc()
+		}
 		return nil, err
 	}
 	return newTimingReadCloser(
 		rc,
-		getRangeOp,
+		op,
 		b.opsDuration,
 		b.opsFailures,
+		b.isOpFailureExpected,
 	), nil
 }
 
 func (b *metricBucket) Exists(ctx context.Context, name string) (bool, error) {
-	start := time.Now()
+	const op = existsOp
+	b.ops.WithLabelValues(op).Inc()
 
+	start := time.Now()
 	ok, err := b.bkt.Exists(ctx, name)
 	if err != nil {
-		b.opsFailures.WithLabelValues(existsOp).Inc()
+		if !b.isOpFailureExpected(err) {
+			b.opsFailures.WithLabelValues(op).Inc()
+		}
+		return false, err
 	}
-	b.ops.WithLabelValues(existsOp).Inc()
-	b.opsDuration.WithLabelValues(existsOp).Observe(time.Since(start).Seconds())
-
-	return ok, err
+	b.opsDuration.WithLabelValues(op).Observe(time.Since(start).Seconds())
+	return ok, nil
 }
 
 func (b *metricBucket) Upload(ctx context.Context, name string, r io.Reader) error {
-	start := time.Now()
+	const op = uploadOp
+	b.ops.WithLabelValues(op).Inc()
 
-	err := b.bkt.Upload(ctx, name, r)
-	if err != nil {
-		b.opsFailures.WithLabelValues(uploadOp).Inc()
-	} else {
-		b.lastSuccessfulUploadTime.WithLabelValues(b.bkt.Name()).SetToCurrentTime()
+	start := time.Now()
+	if err := b.bkt.Upload(ctx, name, r); err != nil {
+		if !b.isOpFailureExpected(err) {
+			b.opsFailures.WithLabelValues(op).Inc()
+		}
+		return err
 	}
-	b.ops.WithLabelValues(uploadOp).Inc()
-	b.opsDuration.WithLabelValues(uploadOp).Observe(time.Since(start).Seconds())
-
-	return err
+	b.lastSuccessfulUploadTime.WithLabelValues(b.bkt.Name()).SetToCurrentTime()
+	b.opsDuration.WithLabelValues(op).Observe(time.Since(start).Seconds())
+	return nil
 }
 
 func (b *metricBucket) Delete(ctx context.Context, name string) error {
-	start := time.Now()
+	const op = deleteOp
+	b.ops.WithLabelValues(op).Inc()
 
-	err := b.bkt.Delete(ctx, name)
-	if err != nil {
-		b.opsFailures.WithLabelValues(deleteOp).Inc()
+	start := time.Now()
+	if err := b.bkt.Delete(ctx, name); err != nil {
+		if !b.isOpFailureExpected(err) {
+			b.opsFailures.WithLabelValues(op).Inc()
+		}
+		return err
 	}
-	b.ops.WithLabelValues(deleteOp).Inc()
-	b.opsDuration.WithLabelValues(deleteOp).Observe(time.Since(start).Seconds())
+	b.opsDuration.WithLabelValues(op).Observe(time.Since(start).Seconds())
 
-	return err
+	return nil
 }
 
 func (b *metricBucket) IsObjNotFoundErr(err error) bool {
@@ -359,53 +427,49 @@ func (b *metricBucket) Name() string {
 type timingReadCloser struct {
 	io.ReadCloser
 
-	ok       bool
-	start    time.Time
-	op       string
-	duration *prometheus.HistogramVec
-	failed   *prometheus.CounterVec
+	alreadyGotErr bool
+
+	start             time.Time
+	op                string
+	duration          *prometheus.HistogramVec
+	failed            *prometheus.CounterVec
+	isFailureExpected IsOpFailureExpectedFunc
 }
 
-func newTimingReadCloser(rc io.ReadCloser, op string, dur *prometheus.HistogramVec, failed *prometheus.CounterVec) *timingReadCloser {
+func newTimingReadCloser(rc io.ReadCloser, op string, dur *prometheus.HistogramVec, failed *prometheus.CounterVec, isFailureExpected IsOpFailureExpectedFunc) *timingReadCloser {
 	// Initialize the metrics with 0.
 	dur.WithLabelValues(op)
 	failed.WithLabelValues(op)
 	return &timingReadCloser{
-		ReadCloser: rc,
-		ok:         true,
-		start:      time.Now(),
-		op:         op,
-		duration:   dur,
-		failed:     failed,
+		ReadCloser:        rc,
+		start:             time.Now(),
+		op:                op,
+		duration:          dur,
+		failed:            failed,
+		isFailureExpected: isFailureExpected,
 	}
 }
 
 func (rc *timingReadCloser) Close() error {
 	err := rc.ReadCloser.Close()
-	rc.duration.WithLabelValues(rc.op).Observe(time.Since(rc.start).Seconds())
-	if rc.ok && err != nil {
+	if !rc.alreadyGotErr && err != nil {
 		rc.failed.WithLabelValues(rc.op).Inc()
-		rc.ok = false
+	}
+	if !rc.alreadyGotErr && err == nil {
+		rc.duration.WithLabelValues(rc.op).Observe(time.Since(rc.start).Seconds())
+		rc.alreadyGotErr = true
 	}
 	return err
 }
 
 func (rc *timingReadCloser) Read(b []byte) (n int, err error) {
 	n, err = rc.ReadCloser.Read(b)
-	if rc.ok && err != nil && err != io.EOF {
-		rc.failed.WithLabelValues(rc.op).Inc()
-		rc.ok = false
+	// Report metric just once.
+	if !rc.alreadyGotErr && err != nil && err != io.EOF {
+		if !rc.isFailureExpected(err) {
+			rc.failed.WithLabelValues(rc.op).Inc()
+		}
+		rc.alreadyGotErr = true
 	}
 	return n, err
 }
-
-func CreateTemporaryTestBucketName(t testing.TB) string {
-	src := rand.NewSource(time.Now().UnixNano())
-
-	// Bucket name need to conform: https://docs.aws.amazon.com/awscloudtrail/latest/userguide/cloudtrail-s3-bucket-naming-requirements.html.
-	name := strings.Replace(strings.Replace(fmt.Sprintf("test_%x_%s", src.Int63(), strings.ToLower(t.Name())), "_", "-", -1), "/", "-", -1)
-	if len(name) >= 63 {
-		name = name[:63]
-	}
-	return name
-}
diff --git a/pkg/objstore/objstore_test.go b/pkg/objstore/objstore_test.go
new file mode 100644
index 00000000000..173bf3d6999
--- /dev/null
+++ b/pkg/objstore/objstore_test.go
@@ -0,0 +1,61 @@
+package objstore
+
+import (
+	"testing"
+
+	promtest "github.com/prometheus/client_golang/prometheus/testutil"
+	"github.com/thanos-io/thanos/pkg/testutil"
+)
+
+func TestMetricBucket_Close(t *testing.T) {
+	bkt := BucketWithMetrics("abc", NewInMemBucket(), nil)
+	// Expected initialized metrics
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.ops))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.opsFailures))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.opsDuration))
+
+	AcceptanceTest(t, bkt.WithExpectedErrs(bkt.IsObjNotFoundErr))
+	testutil.Equals(t, float64(6), promtest.ToFloat64(bkt.ops.WithLabelValues(iterOp)))
+	testutil.Equals(t, float64(2), promtest.ToFloat64(bkt.ops.WithLabelValues(sizeOp)))
+	testutil.Equals(t, float64(3), promtest.ToFloat64(bkt.ops.WithLabelValues(getOp)))
+	testutil.Equals(t, float64(3), promtest.ToFloat64(bkt.ops.WithLabelValues(getRangeOp)))
+	testutil.Equals(t, float64(2), promtest.ToFloat64(bkt.ops.WithLabelValues(existsOp)))
+	testutil.Equals(t, float64(6), promtest.ToFloat64(bkt.ops.WithLabelValues(uploadOp)))
+	testutil.Equals(t, float64(2), promtest.ToFloat64(bkt.ops.WithLabelValues(deleteOp)))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.ops))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(iterOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(sizeOp)))
+	testutil.Equals(t, float64(1), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(getOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(getRangeOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(existsOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(uploadOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(deleteOp)))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.opsFailures))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.opsDuration))
+	lastUpload := promtest.ToFloat64(bkt.lastSuccessfulUploadTime)
+	testutil.Assert(t, lastUpload > 0, "last upload not greater than 0, val: %f", lastUpload)
+
+	// Clear bucket, but don't clear metrics to ensure we use same.
+	bkt.bkt = NewInMemBucket()
+	AcceptanceTest(t, bkt)
+	testutil.Equals(t, float64(12), promtest.ToFloat64(bkt.ops.WithLabelValues(iterOp)))
+	testutil.Equals(t, float64(4), promtest.ToFloat64(bkt.ops.WithLabelValues(sizeOp)))
+	testutil.Equals(t, float64(6), promtest.ToFloat64(bkt.ops.WithLabelValues(getOp)))
+	testutil.Equals(t, float64(6), promtest.ToFloat64(bkt.ops.WithLabelValues(getRangeOp)))
+	testutil.Equals(t, float64(4), promtest.ToFloat64(bkt.ops.WithLabelValues(existsOp)))
+	testutil.Equals(t, float64(12), promtest.ToFloat64(bkt.ops.WithLabelValues(uploadOp)))
+	testutil.Equals(t, float64(4), promtest.ToFloat64(bkt.ops.WithLabelValues(deleteOp)))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.ops))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(iterOp)))
+	// Not expected not found error here.
+	testutil.Equals(t, float64(1), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(sizeOp)))
+	// Not expected not found errors, this should increment failure metric on get for not found as well, so +2.
+	testutil.Equals(t, float64(3), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(getOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(getRangeOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(existsOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(uploadOp)))
+	testutil.Equals(t, float64(0), promtest.ToFloat64(bkt.opsFailures.WithLabelValues(deleteOp)))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.opsFailures))
+	testutil.Equals(t, 7, promtest.CollectAndCount(bkt.opsDuration))
+	testutil.Assert(t, promtest.ToFloat64(bkt.lastSuccessfulUploadTime) > lastUpload)
+}
diff --git a/pkg/objstore/objtesting/acceptance_e2e_test.go b/pkg/objstore/objtesting/acceptance_e2e_test.go
index 86045424eea..4cfda44c337 100644
--- a/pkg/objstore/objtesting/acceptance_e2e_test.go
+++ b/pkg/objstore/objtesting/acceptance_e2e_test.go
@@ -4,14 +4,9 @@
 package objtesting
 
 import (
-	"context"
-	"io/ioutil"
-	"sort"
-	"strings"
 	"testing"
 
 	"github.com/thanos-io/thanos/pkg/objstore"
-	"github.com/thanos-io/thanos/pkg/testutil"
 )
 
 // TestObjStoreAcceptanceTest_e2e tests all known implementation against interface behaviour contract we agreed on.
@@ -19,142 +14,5 @@ import (
 // NOTE: This test assumes strong consistency, but in the same way it does not guarantee that if it passes, the
 // used object store is strongly consistent.
 func TestObjStore_AcceptanceTest_e2e(t *testing.T) {
-	ForeachStore(t, func(t *testing.T, bkt objstore.Bucket) {
-		ctx := context.Background()
-
-		_, err := bkt.Get(ctx, "")
-		testutil.NotOk(t, err)
-		testutil.Assert(t, !bkt.IsObjNotFoundErr(err), "expected user error got not found %s", err)
-
-		_, err = bkt.Get(ctx, "id1/obj_1.some")
-		testutil.NotOk(t, err)
-		testutil.Assert(t, bkt.IsObjNotFoundErr(err), "expected not found error got %s", err)
-
-		ok, err := bkt.Exists(ctx, "id1/obj_1.some")
-		testutil.Ok(t, err)
-		testutil.Assert(t, !ok, "expected not exits")
-
-		_, err = bkt.ObjectSize(ctx, "id1/obj_1.some")
-		testutil.NotOk(t, err)
-		testutil.Assert(t, bkt.IsObjNotFoundErr(err), "expected not found error but got %s", err)
-
-		// Upload first object.
-		testutil.Ok(t, bkt.Upload(ctx, "id1/obj_1.some", strings.NewReader("@test-data@")))
-
-		// Double check we can immediately read it.
-		rc1, err := bkt.Get(ctx, "id1/obj_1.some")
-		testutil.Ok(t, err)
-		defer func() { testutil.Ok(t, rc1.Close()) }()
-		content, err := ioutil.ReadAll(rc1)
-		testutil.Ok(t, err)
-		testutil.Equals(t, "@test-data@", string(content))
-
-		// Check if we can get the correct size.
-		sz, err := bkt.ObjectSize(ctx, "id1/obj_1.some")
-		testutil.Ok(t, err)
-		testutil.Assert(t, sz == 11, "expected size to be equal to 11")
-
-		rc2, err := bkt.GetRange(ctx, "id1/obj_1.some", 1, 3)
-		testutil.Ok(t, err)
-		defer func() { testutil.Ok(t, rc2.Close()) }()
-		content, err = ioutil.ReadAll(rc2)
-		testutil.Ok(t, err)
-		testutil.Equals(t, "tes", string(content))
-
-		// Unspecified range with offset.
-		rcUnspecifiedLen, err := bkt.GetRange(ctx, "id1/obj_1.some", 1, -1)
-		testutil.Ok(t, err)
-		defer func() { testutil.Ok(t, rcUnspecifiedLen.Close()) }()
-		content, err = ioutil.ReadAll(rcUnspecifiedLen)
-		testutil.Ok(t, err)
-		testutil.Equals(t, "test-data@", string(content))
-
-		// Out of band offset. Do not rely on outcome.
-		// NOTE: For various providers we have different outcome.
-		// * GCS is giving 416 status code
-		// * S3 errors immdiately with invalid range error.
-		// * inmem and filesystem are returning 0 bytes.
-		//rcOffset, err := bkt.GetRange(ctx, "id1/obj_1.some", 124141, 3)
-
-		// Out of band length. We expect to read file fully.
-		rcLength, err := bkt.GetRange(ctx, "id1/obj_1.some", 3, 9999)
-		testutil.Ok(t, err)
-		defer func() { testutil.Ok(t, rcLength.Close()) }()
-		content, err = ioutil.ReadAll(rcLength)
-		testutil.Ok(t, err)
-		testutil.Equals(t, "st-data@", string(content))
-
-		ok, err = bkt.Exists(ctx, "id1/obj_1.some")
-		testutil.Ok(t, err)
-		testutil.Assert(t, ok, "expected exits")
-
-		// Upload other objects.
-		testutil.Ok(t, bkt.Upload(ctx, "id1/obj_2.some", strings.NewReader("@test-data2@")))
-		// Upload should be idempotent.
-		testutil.Ok(t, bkt.Upload(ctx, "id1/obj_2.some", strings.NewReader("@test-data2@")))
-		testutil.Ok(t, bkt.Upload(ctx, "id1/obj_3.some", strings.NewReader("@test-data3@")))
-		testutil.Ok(t, bkt.Upload(ctx, "id2/obj_4.some", strings.NewReader("@test-data4@")))
-		testutil.Ok(t, bkt.Upload(ctx, "obj_5.some", strings.NewReader("@test-data5@")))
-
-		// Can we iter over items from top dir?
-		var seen []string
-		testutil.Ok(t, bkt.Iter(ctx, "", func(fn string) error {
-			seen = append(seen, fn)
-			return nil
-		}))
-		expected := []string{"obj_5.some", "id1/", "id2/"}
-		sort.Strings(expected)
-		sort.Strings(seen)
-		testutil.Equals(t, expected, seen)
-
-		// Can we iter over items from id1/ dir?
-		seen = []string{}
-		testutil.Ok(t, bkt.Iter(ctx, "id1/", func(fn string) error {
-			seen = append(seen, fn)
-			return nil
-		}))
-		testutil.Equals(t, []string{"id1/obj_1.some", "id1/obj_2.some", "id1/obj_3.some"}, seen)
-
-		// Can we iter over items from id1 dir?
-		seen = []string{}
-		testutil.Ok(t, bkt.Iter(ctx, "id1", func(fn string) error {
-			seen = append(seen, fn)
-			return nil
-		}))
-		testutil.Equals(t, []string{"id1/obj_1.some", "id1/obj_2.some", "id1/obj_3.some"}, seen)
-
-		// Can we iter over items from not existing dir?
-		testutil.Ok(t, bkt.Iter(ctx, "id0", func(fn string) error {
-			t.Error("Not expected to loop through not existing directory")
-			t.FailNow()
-
-			return nil
-		}))
-
-		testutil.Ok(t, bkt.Delete(ctx, "id1/obj_2.some"))
-
-		// Delete is expected to fail on non existing object.
-		// NOTE: Don't rely on this. S3 is not complying with this as GCS is.
-		// testutil.NotOk(t, bkt.Delete(ctx, "id1/obj_2.some"))
-
-		// Can we iter over items from id1/ dir and see obj2 being deleted?
-		seen = []string{}
-		testutil.Ok(t, bkt.Iter(ctx, "id1/", func(fn string) error {
-			seen = append(seen, fn)
-			return nil
-		}))
-		testutil.Equals(t, []string{"id1/obj_1.some", "id1/obj_3.some"}, seen)
-
-		testutil.Ok(t, bkt.Delete(ctx, "id2/obj_4.some"))
-
-		seen = []string{}
-		testutil.Ok(t, bkt.Iter(ctx, "", func(fn string) error {
-			seen = append(seen, fn)
-			return nil
-		}))
-		expected = []string{"obj_5.some", "id1/"}
-		sort.Strings(expected)
-		sort.Strings(seen)
-		testutil.Equals(t, expected, seen)
-	})
+	ForeachStore(t, objstore.AcceptanceTest)
 }
diff --git a/pkg/objstore/objtesting/foreach.go b/pkg/objstore/objtesting/foreach.go
index 97b0490977c..e0c28cb4f6d 100644
--- a/pkg/objstore/objtesting/foreach.go
+++ b/pkg/objstore/objtesting/foreach.go
@@ -16,7 +16,6 @@ import (
 	"github.com/thanos-io/thanos/pkg/objstore/azure"
 	"github.com/thanos-io/thanos/pkg/objstore/cos"
 	"github.com/thanos-io/thanos/pkg/objstore/gcs"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
 	"github.com/thanos-io/thanos/pkg/objstore/oss"
 	"github.com/thanos-io/thanos/pkg/objstore/s3"
 	"github.com/thanos-io/thanos/pkg/objstore/swift"
@@ -48,7 +47,7 @@ func ForeachStore(t *testing.T, testFn func(t *testing.T, bkt objstore.Bucket))
 
 	// Mandatory Inmem. Not parallel, to detect problem early.
 	if ok := t.Run("inmem", func(t *testing.T) {
-		testFn(t, inmem.NewBucket())
+		testFn(t, objstore.NewInMemBucket())
 	}); !ok {
 		return
 	}
diff --git a/pkg/objstore/oss/oss.go b/pkg/objstore/oss/oss.go
index 5c081d7a5a1..8a8d72086c9 100644
--- a/pkg/objstore/oss/oss.go
+++ b/pkg/objstore/oss/oss.go
@@ -150,7 +150,7 @@ func (b *Bucket) ObjectSize(ctx context.Context, name string) (uint64, error) {
 	return 0, errors.New("content-length header not found")
 }
 
-// NewBucket returns a new Bucket using the provided oss config values.
+// NewInMemBucket returns a new Bucket using the provided oss config values.
 func NewBucket(logger log.Logger, conf []byte, component string) (*Bucket, error) {
 	var config Config
 	if err := yaml.Unmarshal(conf, &config); err != nil {
diff --git a/pkg/objstore/s3/s3.go b/pkg/objstore/s3/s3.go
index 285bebaf7d1..0d87f2cb1e5 100644
--- a/pkg/objstore/s3/s3.go
+++ b/pkg/objstore/s3/s3.go
@@ -93,7 +93,7 @@ func parseConfig(conf []byte) (Config, error) {
 	return config, nil
 }
 
-// NewBucket returns a new Bucket using the provided s3 config values.
+// NewInMemBucket returns a new Bucket using the provided s3 config values.
 func NewBucket(logger log.Logger, conf []byte, component string) (*Bucket, error) {
 	config, err := parseConfig(conf)
 	if err != nil {
diff --git a/pkg/objstore/testing.go b/pkg/objstore/testing.go
index 9e9a864b915..e7886ea7207 100644
--- a/pkg/objstore/testing.go
+++ b/pkg/objstore/testing.go
@@ -5,11 +5,29 @@ package objstore
 
 import (
 	"context"
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"sort"
 	"strings"
 	"sync"
 	"testing"
+	"time"
+
+	"github.com/thanos-io/thanos/pkg/testutil"
 )
 
+func CreateTemporaryTestBucketName(t testing.TB) string {
+	src := rand.NewSource(time.Now().UnixNano())
+
+	// Bucket name need to conform: https://docs.aws.amazon.com/awscloudtrail/latest/userguide/cloudtrail-s3-bucket-naming-requirements.html.
+	name := strings.Replace(strings.Replace(fmt.Sprintf("test_%x_%s", src.Int63(), strings.ToLower(t.Name())), "_", "-", -1), "/", "-", -1)
+	if len(name) >= 63 {
+		name = name[:63]
+	}
+	return name
+}
+
 // EmptyBucket deletes all objects from bucket. This operation is required to properly delete bucket as a whole.
 // It is used for testing only.
 // TODO(bplotka): Add retries.
@@ -44,3 +62,154 @@ func EmptyBucket(t testing.TB, ctx context.Context, bkt Bucket) {
 	}
 	wg.Wait()
 }
+
+type NoopInstrumentedBucket struct {
+	Bucket
+}
+
+func (b NoopInstrumentedBucket) WithExpectedErrs(IsOpFailureExpectedFunc) Bucket {
+	return b
+}
+
+func (b NoopInstrumentedBucket) ReaderWithExpectedErrs(IsOpFailureExpectedFunc) BucketReader {
+	return b
+}
+
+func AcceptanceTest(t *testing.T, bkt Bucket) {
+	ctx := context.Background()
+
+	_, err := bkt.Get(ctx, "")
+	testutil.NotOk(t, err)
+	testutil.Assert(t, !bkt.IsObjNotFoundErr(err), "expected user error got not found %s", err)
+
+	_, err = bkt.Get(ctx, "id1/obj_1.some")
+	testutil.NotOk(t, err)
+	testutil.Assert(t, bkt.IsObjNotFoundErr(err), "expected not found error got %s", err)
+
+	ok, err := bkt.Exists(ctx, "id1/obj_1.some")
+	testutil.Ok(t, err)
+	testutil.Assert(t, !ok, "expected not exits")
+
+	_, err = bkt.ObjectSize(ctx, "id1/obj_1.some")
+	testutil.NotOk(t, err)
+	testutil.Assert(t, bkt.IsObjNotFoundErr(err), "expected not found error but got %s", err)
+
+	// Upload first object.
+	testutil.Ok(t, bkt.Upload(ctx, "id1/obj_1.some", strings.NewReader("@test-data@")))
+
+	// Double check we can immediately read it.
+	rc1, err := bkt.Get(ctx, "id1/obj_1.some")
+	testutil.Ok(t, err)
+	defer func() { testutil.Ok(t, rc1.Close()) }()
+	content, err := ioutil.ReadAll(rc1)
+	testutil.Ok(t, err)
+	testutil.Equals(t, "@test-data@", string(content))
+
+	// Check if we can get the correct size.
+	sz, err := bkt.ObjectSize(ctx, "id1/obj_1.some")
+	testutil.Ok(t, err)
+	testutil.Assert(t, sz == 11, "expected size to be equal to 11")
+
+	rc2, err := bkt.GetRange(ctx, "id1/obj_1.some", 1, 3)
+	testutil.Ok(t, err)
+	defer func() { testutil.Ok(t, rc2.Close()) }()
+	content, err = ioutil.ReadAll(rc2)
+	testutil.Ok(t, err)
+	testutil.Equals(t, "tes", string(content))
+
+	// Unspecified range with offset.
+	rcUnspecifiedLen, err := bkt.GetRange(ctx, "id1/obj_1.some", 1, -1)
+	testutil.Ok(t, err)
+	defer func() { testutil.Ok(t, rcUnspecifiedLen.Close()) }()
+	content, err = ioutil.ReadAll(rcUnspecifiedLen)
+	testutil.Ok(t, err)
+	testutil.Equals(t, "test-data@", string(content))
+
+	// Out of band offset. Do not rely on outcome.
+	// NOTE: For various providers we have different outcome.
+	// * GCS is giving 416 status code
+	// * S3 errors immdiately with invalid range error.
+	// * inmem and filesystem are returning 0 bytes.
+	//rcOffset, err := bkt.GetRange(ctx, "id1/obj_1.some", 124141, 3)
+
+	// Out of band length. We expect to read file fully.
+	rcLength, err := bkt.GetRange(ctx, "id1/obj_1.some", 3, 9999)
+	testutil.Ok(t, err)
+	defer func() { testutil.Ok(t, rcLength.Close()) }()
+	content, err = ioutil.ReadAll(rcLength)
+	testutil.Ok(t, err)
+	testutil.Equals(t, "st-data@", string(content))
+
+	ok, err = bkt.Exists(ctx, "id1/obj_1.some")
+	testutil.Ok(t, err)
+	testutil.Assert(t, ok, "expected exits")
+
+	// Upload other objects.
+	testutil.Ok(t, bkt.Upload(ctx, "id1/obj_2.some", strings.NewReader("@test-data2@")))
+	// Upload should be idempotent.
+	testutil.Ok(t, bkt.Upload(ctx, "id1/obj_2.some", strings.NewReader("@test-data2@")))
+	testutil.Ok(t, bkt.Upload(ctx, "id1/obj_3.some", strings.NewReader("@test-data3@")))
+	testutil.Ok(t, bkt.Upload(ctx, "id2/obj_4.some", strings.NewReader("@test-data4@")))
+	testutil.Ok(t, bkt.Upload(ctx, "obj_5.some", strings.NewReader("@test-data5@")))
+
+	// Can we iter over items from top dir?
+	var seen []string
+	testutil.Ok(t, bkt.Iter(ctx, "", func(fn string) error {
+		seen = append(seen, fn)
+		return nil
+	}))
+	expected := []string{"obj_5.some", "id1/", "id2/"}
+	sort.Strings(expected)
+	sort.Strings(seen)
+	testutil.Equals(t, expected, seen)
+
+	// Can we iter over items from id1/ dir?
+	seen = []string{}
+	testutil.Ok(t, bkt.Iter(ctx, "id1/", func(fn string) error {
+		seen = append(seen, fn)
+		return nil
+	}))
+	testutil.Equals(t, []string{"id1/obj_1.some", "id1/obj_2.some", "id1/obj_3.some"}, seen)
+
+	// Can we iter over items from id1 dir?
+	seen = []string{}
+	testutil.Ok(t, bkt.Iter(ctx, "id1", func(fn string) error {
+		seen = append(seen, fn)
+		return nil
+	}))
+	testutil.Equals(t, []string{"id1/obj_1.some", "id1/obj_2.some", "id1/obj_3.some"}, seen)
+
+	// Can we iter over items from not existing dir?
+	testutil.Ok(t, bkt.Iter(ctx, "id0", func(fn string) error {
+		t.Error("Not expected to loop through not existing directory")
+		t.FailNow()
+
+		return nil
+	}))
+
+	testutil.Ok(t, bkt.Delete(ctx, "id1/obj_2.some"))
+
+	// Delete is expected to fail on non existing object.
+	// NOTE: Don't rely on this. S3 is not complying with this as GCS is.
+	// testutil.NotOk(t, bkt.Delete(ctx, "id1/obj_2.some"))
+
+	// Can we iter over items from id1/ dir and see obj2 being deleted?
+	seen = []string{}
+	testutil.Ok(t, bkt.Iter(ctx, "id1/", func(fn string) error {
+		seen = append(seen, fn)
+		return nil
+	}))
+	testutil.Equals(t, []string{"id1/obj_1.some", "id1/obj_3.some"}, seen)
+
+	testutil.Ok(t, bkt.Delete(ctx, "id2/obj_4.some"))
+
+	seen = []string{}
+	testutil.Ok(t, bkt.Iter(ctx, "", func(fn string) error {
+		seen = append(seen, fn)
+		return nil
+	}))
+	expected = []string{"obj_5.some", "id1/"}
+	sort.Strings(expected)
+	sort.Strings(seen)
+	testutil.Equals(t, expected, seen)
+}
diff --git a/pkg/replicate/scheme.go b/pkg/replicate/scheme.go
index ba5fa113ba3..5402dd9a78e 100644
--- a/pkg/replicate/scheme.go
+++ b/pkg/replicate/scheme.go
@@ -101,7 +101,7 @@ type blockFilterFunc func(b *metadata.Meta) bool
 
 // TODO: Add filters field.
 type replicationScheme struct {
-	fromBkt objstore.BucketReader
+	fromBkt objstore.InstrumentedBucketReader
 	toBkt   objstore.Bucket
 
 	blockFilter blockFilterFunc
@@ -158,7 +158,7 @@ func newReplicationScheme(
 	metrics *replicationMetrics,
 	blockFilter blockFilterFunc,
 	fetcher thanosblock.MetadataFetcher,
-	from objstore.BucketReader,
+	from objstore.InstrumentedBucketReader,
 	to objstore.Bucket,
 	reg prometheus.Registerer,
 ) *replicationScheme {
@@ -254,7 +254,7 @@ func (rs *replicationScheme) ensureBlockIsReplicated(ctx context.Context, id uli
 
 	level.Debug(rs.logger).Log("msg", "ensuring block is replicated", "block_uuid", blockID)
 
-	originMetaFile, err := rs.fromBkt.Get(ctx, metaFile)
+	originMetaFile, err := rs.fromBkt.ReaderWithExpectedErrs(rs.fromBkt.IsObjNotFoundErr).Get(ctx, metaFile)
 	if err != nil {
 		return errors.Wrap(err, "get meta file from origin bucket")
 	}
diff --git a/pkg/replicate/scheme_test.go b/pkg/replicate/scheme_test.go
index 26c83aafb64..58cd3a9b1f9 100644
--- a/pkg/replicate/scheme_test.go
+++ b/pkg/replicate/scheme_test.go
@@ -23,7 +23,6 @@ import (
 	"github.com/thanos-io/thanos/pkg/block/metadata"
 	"github.com/thanos-io/thanos/pkg/compact"
 	"github.com/thanos-io/thanos/pkg/objstore"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
 	"github.com/thanos-io/thanos/pkg/testutil"
 )
 
@@ -66,20 +65,20 @@ func TestReplicationSchemeAll(t *testing.T) {
 	var cases = []struct {
 		name     string
 		selector labels.Selector
-		prepare  func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket)
-		assert   func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket)
+		prepare  func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket)
+		assert   func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket)
 	}{
 		{
 			name:    "EmptyOrigin",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {},
-			assert:  func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {},
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {},
+			assert:  func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {},
 		},
 		{
 			name: "NoMeta",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				_ = originBucket.Upload(ctx, path.Join(testULID(0).String(), "chunks", "000001"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				if len(targetBucket.Objects()) != 0 {
 					t.Fatal("TargetBucket should have been empty but is not.")
 				}
@@ -87,10 +86,10 @@ func TestReplicationSchemeAll(t *testing.T) {
 		},
 		{
 			name: "PartialMeta",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				_ = originBucket.Upload(ctx, path.Join(testULID(0).String(), "meta.json"), bytes.NewReader([]byte("{")))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				if len(targetBucket.Objects()) != 0 {
 					t.Fatal("TargetBucket should have been empty but is not.")
 				}
@@ -98,7 +97,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		},
 		{
 			name: "FullBlock",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				ulid := testULID(0)
 				meta := testMeta(ulid)
 
@@ -108,7 +107,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "chunks", "000001"), bytes.NewReader(nil))
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "index"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				if len(targetBucket.Objects()) != 3 {
 					t.Fatal("TargetBucket should have one block made up of three objects replicated.")
 				}
@@ -116,7 +115,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		},
 		{
 			name: "PreviousPartialUpload",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				ulid := testULID(0)
 				meta := testMeta(ulid)
 
@@ -130,7 +129,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 				_ = targetBucket.Upload(ctx, path.Join(ulid.String(), "chunks", "000001"), bytes.NewReader(nil))
 				_ = targetBucket.Upload(ctx, path.Join(ulid.String(), "index"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				for k := range originBucket.Objects() {
 					if !bytes.Equal(originBucket.Objects()[k], targetBucket.Objects()[k]) {
 						t.Fatalf("Object %s not equal in origin and target bucket.", k)
@@ -140,7 +139,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		},
 		{
 			name: "OnlyUploadsRaw",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				ulid := testULID(0)
 				meta := testMeta(ulid)
 
@@ -160,7 +159,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "chunks", "000001"), bytes.NewReader(nil))
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "index"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				expected := 3
 				got := len(targetBucket.Objects())
 				if got != expected {
@@ -170,7 +169,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		},
 		{
 			name: "UploadMultipleCandidatesWhenPresent",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				ulid := testULID(0)
 				meta := testMeta(ulid)
 
@@ -189,7 +188,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "chunks", "000001"), bytes.NewReader(nil))
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "index"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				expected := 6
 				got := len(targetBucket.Objects())
 				if got != expected {
@@ -199,7 +198,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		},
 		{
 			name: "LabelSelector",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				ulid := testULID(0)
 				meta := testMeta(ulid)
 
@@ -219,7 +218,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "chunks", "000001"), bytes.NewReader(nil))
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "index"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				expected := 3
 				got := len(targetBucket.Objects())
 				if got != expected {
@@ -229,7 +228,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		},
 		{
 			name: "NonZeroCompaction",
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				ulid := testULID(0)
 				meta := testMeta(ulid)
 				meta.BlockMeta.Compaction.Level = 2
@@ -240,7 +239,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "chunks", "000001"), bytes.NewReader(nil))
 				_ = originBucket.Upload(ctx, path.Join(ulid.String(), "index"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				if len(targetBucket.Objects()) != 0 {
 					t.Fatal("TargetBucket should have been empty but is not.")
 				}
@@ -249,7 +248,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		{
 			name:     "Regression",
 			selector: labels.Selector{},
-			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket objstore.Bucket) {
+			prepare: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				b := []byte(`{
         "ulid": "01DQYXMK8G108CEBQ79Y84DYVY",
         "minTime": 1571911200000,
@@ -282,7 +281,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 				_ = originBucket.Upload(ctx, path.Join("01DQYXMK8G108CEBQ79Y84DYVY", "chunks", "000001"), bytes.NewReader(nil))
 				_ = originBucket.Upload(ctx, path.Join("01DQYXMK8G108CEBQ79Y84DYVY", "index"), bytes.NewReader(nil))
 			},
-			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *inmem.Bucket) {
+			assert: func(ctx context.Context, t *testing.T, originBucket, targetBucket *objstore.InMemBucket) {
 				if len(targetBucket.Objects()) != 3 {
 					t.Fatal("TargetBucket should have one block does not.")
 				}
@@ -296,8 +295,8 @@ func TestReplicationSchemeAll(t *testing.T) {
 
 	for _, c := range cases {
 		ctx := context.Background()
-		originBucket := inmem.NewBucket()
-		targetBucket := inmem.NewBucket()
+		originBucket := objstore.NewInMemBucket()
+		targetBucket := objstore.NewInMemBucket()
 		logger := testLogger(t.Name() + "/" + c.name)
 
 		c.prepare(ctx, t, originBucket, targetBucket)
@@ -313,7 +312,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 		}
 
 		filter := NewBlockFilter(logger, selector, compact.ResolutionLevelRaw, 1).Filter
-		fetcher, err := block.NewMetaFetcher(logger, 32, originBucket, "", nil, nil, nil)
+		fetcher, err := block.NewMetaFetcher(logger, 32, objstore.NoopInstrumentedBucket{originBucket}, "", nil, nil, nil)
 		testutil.Ok(t, err)
 
 		r := newReplicationScheme(
@@ -321,7 +320,7 @@ func TestReplicationSchemeAll(t *testing.T) {
 			newReplicationMetrics(nil),
 			filter,
 			fetcher,
-			originBucket,
+			objstore.NoopInstrumentedBucket{originBucket},
 			targetBucket,
 			nil,
 		)
diff --git a/pkg/shipper/shipper_e2e_test.go b/pkg/shipper/shipper_e2e_test.go
index 19695426f23..b307b165328 100644
--- a/pkg/shipper/shipper_e2e_test.go
+++ b/pkg/shipper/shipper_e2e_test.go
@@ -15,7 +15,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
 	"github.com/thanos-io/thanos/pkg/testutil/e2eutil"
 
 	"github.com/go-kit/kit/log"
@@ -180,7 +179,7 @@ func TestShipper_SyncBlocksWithMigrating_e2e(t *testing.T) {
 			testutil.Ok(t, os.RemoveAll(dir))
 		}()
 
-		bkt := inmem.NewBucket()
+		bkt := objstore.NewInMemBucket()
 
 		ctx, cancel := context.WithCancel(context.Background())
 		defer cancel()
diff --git a/pkg/store/bucket.go b/pkg/store/bucket.go
index 81dcb4ff1e2..4d2704b1fea 100644
--- a/pkg/store/bucket.go
+++ b/pkg/store/bucket.go
@@ -221,7 +221,7 @@ type FilterConfig struct {
 type BucketStore struct {
 	logger     log.Logger
 	metrics    *bucketStoreMetrics
-	bkt        objstore.BucketReader
+	bkt        objstore.InstrumentedBucketReader
 	fetcher    block.MetadataFetcher
 	dir        string
 	indexCache storecache.IndexCache
@@ -260,7 +260,7 @@ type BucketStore struct {
 func NewBucketStore(
 	logger log.Logger,
 	reg prometheus.Registerer,
-	bucket objstore.BucketReader,
+	bkt objstore.InstrumentedBucketReader,
 	fetcher block.MetadataFetcher,
 	dir string,
 	indexCache storecache.IndexCache,
@@ -290,7 +290,7 @@ func NewBucketStore(
 	metrics := newBucketStoreMetrics(reg)
 	s := &BucketStore{
 		logger:               logger,
-		bkt:                  bucket,
+		bkt:                  bkt,
 		fetcher:              fetcher,
 		dir:                  dir,
 		indexCache:           indexCache,
diff --git a/pkg/store/bucket_e2e_test.go b/pkg/store/bucket_e2e_test.go
index 8bcf3216c08..97e6a053b4d 100644
--- a/pkg/store/bucket_e2e_test.go
+++ b/pkg/store/bucket_e2e_test.go
@@ -21,7 +21,6 @@ import (
 	"github.com/thanos-io/thanos/pkg/block/metadata"
 	"github.com/thanos-io/thanos/pkg/model"
 	"github.com/thanos-io/thanos/pkg/objstore"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
 	"github.com/thanos-io/thanos/pkg/objstore/objtesting"
 	storecache "github.com/thanos-io/thanos/pkg/store/cache"
 	"github.com/thanos-io/thanos/pkg/store/storepb"
@@ -147,7 +146,7 @@ func prepareStoreWithTestBlocks(t testing.TB, dir string, bkt objstore.Bucket, m
 		maxTime: maxTime,
 	}
 
-	metaFetcher, err := block.NewMetaFetcher(s.logger, 20, bkt, dir, nil, []block.MetadataFilter{
+	metaFetcher, err := block.NewMetaFetcher(s.logger, 20, objstore.NoopInstrumentedBucket{bkt}, dir, nil, []block.MetadataFilter{
 		block.NewTimePartitionMetaFilter(filterConf.MinTime, filterConf.MaxTime),
 		block.NewLabelShardedMetaFilter(relabelConfig),
 	}, nil)
@@ -156,7 +155,7 @@ func prepareStoreWithTestBlocks(t testing.TB, dir string, bkt objstore.Bucket, m
 	store, err := NewBucketStore(
 		s.logger,
 		nil,
-		bkt,
+		objstore.NoopInstrumentedBucket{bkt},
 		metaFetcher,
 		dir,
 		s.cache,
@@ -497,7 +496,7 @@ func TestBucketStore_ManyParts_e2e(t *testing.T) {
 func TestBucketStore_TimePartitioning_e2e(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
-	bkt := inmem.NewBucket()
+	bkt := objstore.NewInMemBucket()
 
 	dir, err := ioutil.TempDir("", "test_bucket_time_part_e2e")
 	testutil.Ok(t, err)
diff --git a/pkg/store/bucket_test.go b/pkg/store/bucket_test.go
index 516bf684c3a..446256fea96 100644
--- a/pkg/store/bucket_test.go
+++ b/pkg/store/bucket_test.go
@@ -43,7 +43,6 @@ import (
 	"github.com/thanos-io/thanos/pkg/compact/downsample"
 	"github.com/thanos-io/thanos/pkg/objstore"
 	"github.com/thanos-io/thanos/pkg/objstore/filesystem"
-	"github.com/thanos-io/thanos/pkg/objstore/inmem"
 	"github.com/thanos-io/thanos/pkg/pool"
 	storecache "github.com/thanos-io/thanos/pkg/store/cache"
 	"github.com/thanos-io/thanos/pkg/store/storepb"
@@ -526,7 +525,7 @@ func TestBucketStore_Sharding(t *testing.T) {
 	testutil.Ok(t, err)
 	defer func() { testutil.Ok(t, os.RemoveAll(dir)) }()
 
-	bkt := inmem.NewBucket()
+	bkt := objstore.NewInMemBucket()
 	series := []labels.Labels{labels.FromStrings("a", "1", "b", "1")}
 
 	id1, err := e2eutil.CreateBlock(ctx, dir, series, 10, 0, 1000, labels.Labels{{Name: "cluster", Value: "a"}, {Name: "region", Value: "r1"}}, 0)
@@ -711,7 +710,7 @@ func testSharding(t *testing.T, reuseDisk string, bkt objstore.Bucket, all ...ul
 			testutil.Ok(t, yaml.Unmarshal([]byte(sc.relabel), &relabelConf))
 
 			rec := &recorder{Bucket: bkt}
-			metaFetcher, err := block.NewMetaFetcher(logger, 20, bkt, dir, nil, []block.MetadataFilter{
+			metaFetcher, err := block.NewMetaFetcher(logger, 20, objstore.NoopInstrumentedBucket{bkt}, dir, nil, []block.MetadataFilter{
 				block.NewTimePartitionMetaFilter(allowAllFilterConf.MinTime, allowAllFilterConf.MaxTime),
 				block.NewLabelShardedMetaFilter(relabelConf),
 			}, nil)
@@ -720,7 +719,7 @@ func testSharding(t *testing.T, reuseDisk string, bkt objstore.Bucket, all ...ul
 			bucketStore, err := NewBucketStore(
 				logger,
 				nil,
-				rec,
+				objstore.NoopInstrumentedBucket{rec},
 				metaFetcher,
 				dir,
 				noopCache{},
@@ -813,7 +812,7 @@ func expectedTouchedBlockOps(all []ulid.ULID, expected []ulid.ULID, cached []uli
 
 // Regression tests against: https://github.com/thanos-io/thanos/issues/1983.
 func TestReadIndexCache_LoadSeries(t *testing.T) {
-	bkt := inmem.NewBucket()
+	bkt := objstore.NewInMemBucket()
 
 	s := newBucketStoreMetrics(nil)
 	b := &bucketBlock{
@@ -1310,7 +1309,7 @@ func benchSeries(t testutil.TB, number int, dimension Dimension, cases ...int) {
 	}
 
 	store := &BucketStore{
-		bkt:        bkt,
+		bkt:        objstore.NoopInstrumentedBucket{bkt},
 		logger:     logger,
 		indexCache: noopCache{},
 		metrics:    newBucketStoreMetrics(nil),
@@ -1551,7 +1550,7 @@ func TestSeries_OneBlock_InMemIndexCacheSegfault(t *testing.T) {
 	}
 
 	store := &BucketStore{
-		bkt:        bkt,
+		bkt:        objstore.NoopInstrumentedBucket{bkt},
 		logger:     logger,
 		indexCache: indexCache,
 		metrics:    newBucketStoreMetrics(nil),
diff --git a/pkg/testutil/testutil.go b/pkg/testutil/testutil.go
index e1ba298d7eb..8b1e8e1d4f1 100644
--- a/pkg/testutil/testutil.go
+++ b/pkg/testutil/testutil.go
@@ -18,6 +18,7 @@ import (
 
 // Assert fails the test if the condition is false.
 func Assert(tb testing.TB, condition bool, v ...interface{}) {
+	tb.Helper()
 	if condition {
 		return
 	}
@@ -27,11 +28,12 @@ func Assert(tb testing.TB, condition bool, v ...interface{}) {
 	if len(v) > 0 {
 		msg = fmt.Sprintf(v[0].(string), v[1:]...)
 	}
-	tb.Fatalf("\033[31m%s:%d: "+msg+"\033[39m\n\n", append([]interface{}{filepath.Base(file), line}, v...)...)
+	tb.Fatalf("\033[31m%s:%d: "+msg+"\033[39m\n\n", filepath.Base(file), line)
 }
 
 // Ok fails the test if an err is not nil.
 func Ok(tb testing.TB, err error, v ...interface{}) {
+	tb.Helper()
 	if err == nil {
 		return
 	}
@@ -46,6 +48,7 @@ func Ok(tb testing.TB, err error, v ...interface{}) {
 
 // NotOk fails the test if an err is nil.
 func NotOk(tb testing.TB, err error, v ...interface{}) {
+	tb.Helper()
 	if err != nil {
 		return
 	}
@@ -60,6 +63,7 @@ func NotOk(tb testing.TB, err error, v ...interface{}) {
 
 // Equals fails the test if exp is not equal to act.
 func Equals(tb testing.TB, exp, act interface{}, v ...interface{}) {
+	tb.Helper()
 	if reflect.DeepEqual(exp, act) {
 		return
 	}