This repository has been archived by the owner on Aug 13, 2019. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 179
/
db.go
986 lines (853 loc) · 25 KB
/
db.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
// Copyright 2017 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package tsdb implements a time series storage for float64 sample data.
package tsdb
import (
"bytes"
"fmt"
"io"
"io/ioutil"
"math"
"os"
"path/filepath"
"runtime"
"sort"
"strconv"
"strings"
"sync"
"time"
"github.com/go-kit/kit/log"
"github.com/go-kit/kit/log/level"
"github.com/oklog/ulid"
"github.com/pkg/errors"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/tsdb/chunkenc"
"github.com/prometheus/tsdb/fileutil"
"github.com/prometheus/tsdb/labels"
"github.com/prometheus/tsdb/wal"
"golang.org/x/sync/errgroup"
)
// DefaultOptions used for the DB. They are sane for setups using
// millisecond precision timestamps.
var DefaultOptions = &Options{
WALFlushInterval: 5 * time.Second,
RetentionDuration: 15 * 24 * 60 * 60 * 1000, // 15 days in milliseconds
BlockRanges: ExponentialBlockRanges(int64(2*time.Hour)/1e6, 3, 5),
NoLockfile: false,
}
// Options of the DB storage.
type Options struct {
// The interval at which the write ahead log is flushed to disk.
WALFlushInterval time.Duration
// Duration of persisted data to keep.
RetentionDuration uint64
// The sizes of the Blocks.
BlockRanges []int64
// NoLockfile disables creation and consideration of a lock file.
NoLockfile bool
}
// Appender allows appending a batch of data. It must be completed with a
// call to Commit or Rollback and must not be reused afterwards.
//
// Operations on the Appender interface are not goroutine-safe.
type Appender interface {
// Add adds a sample pair for the given series. A reference number is
// returned which can be used to add further samples in the same or later
// transactions.
// Returned reference numbers are ephemeral and may be rejected in calls
// to AddFast() at any point. Adding the sample via Add() returns a new
// reference number.
// If the reference is 0 it must not be used for caching.
Add(l labels.Labels, t int64, v float64) (uint64, error)
// Add adds a sample pair for the referenced series. It is generally faster
// than adding a sample by providing its full label set.
AddFast(ref uint64, t int64, v float64) error
// Commit submits the collected samples and purges the batch.
Commit() error
// Rollback rolls back all modifications made in the appender so far.
Rollback() error
}
// DB handles reads and writes of time series falling into
// a hashed partition of a seriedb.
type DB struct {
dir string
lockf fileutil.Releaser
logger log.Logger
metrics *dbMetrics
opts *Options
chunkPool chunkenc.Pool
compactor Compactor
// Mutex for that must be held when modifying the general block layout.
mtx sync.RWMutex
blocks []*Block
head *Head
compactc chan struct{}
donec chan struct{}
stopc chan struct{}
// cmtx is used to control compactions and deletions.
cmtx sync.Mutex
compactionsEnabled bool
}
type dbMetrics struct {
loadedBlocks prometheus.GaugeFunc
symbolTableSize prometheus.GaugeFunc
reloads prometheus.Counter
reloadsFailed prometheus.Counter
compactionsTriggered prometheus.Counter
cutoffs prometheus.Counter
cutoffsFailed prometheus.Counter
tombCleanTimer prometheus.Histogram
}
func newDBMetrics(db *DB, r prometheus.Registerer) *dbMetrics {
m := &dbMetrics{}
m.loadedBlocks = prometheus.NewGaugeFunc(prometheus.GaugeOpts{
Name: "prometheus_tsdb_blocks_loaded",
Help: "Number of currently loaded data blocks",
}, func() float64 {
db.mtx.RLock()
defer db.mtx.RUnlock()
return float64(len(db.blocks))
})
m.symbolTableSize = prometheus.NewGaugeFunc(prometheus.GaugeOpts{
Name: "prometheus_tsdb_symbol_table_size_bytes",
Help: "Size of symbol table on disk (in bytes)",
}, func() float64 {
db.mtx.RLock()
blocks := db.blocks[:]
db.mtx.RUnlock()
symTblSize := uint64(0)
for _, b := range blocks {
symTblSize += b.GetSymbolTableSize()
}
return float64(symTblSize)
})
m.reloads = prometheus.NewCounter(prometheus.CounterOpts{
Name: "prometheus_tsdb_reloads_total",
Help: "Number of times the database reloaded block data from disk.",
})
m.reloadsFailed = prometheus.NewCounter(prometheus.CounterOpts{
Name: "prometheus_tsdb_reloads_failures_total",
Help: "Number of times the database failed to reload block data from disk.",
})
m.compactionsTriggered = prometheus.NewCounter(prometheus.CounterOpts{
Name: "prometheus_tsdb_compactions_triggered_total",
Help: "Total number of triggered compactions for the partition.",
})
m.cutoffs = prometheus.NewCounter(prometheus.CounterOpts{
Name: "prometheus_tsdb_retention_cutoffs_total",
Help: "Number of times the database cut off block data from disk.",
})
m.cutoffsFailed = prometheus.NewCounter(prometheus.CounterOpts{
Name: "prometheus_tsdb_retention_cutoffs_failures_total",
Help: "Number of times the database failed to cut off block data from disk.",
})
m.tombCleanTimer = prometheus.NewHistogram(prometheus.HistogramOpts{
Name: "prometheus_tsdb_tombstone_cleanup_seconds",
Help: "The time taken to recompact blocks to remove tombstones.",
})
if r != nil {
r.MustRegister(
m.loadedBlocks,
m.symbolTableSize,
m.reloads,
m.reloadsFailed,
m.cutoffs,
m.cutoffsFailed,
m.compactionsTriggered,
m.tombCleanTimer,
)
}
return m
}
// Open returns a new DB in the given directory.
func Open(dir string, l log.Logger, r prometheus.Registerer, opts *Options) (db *DB, err error) {
if err := os.MkdirAll(dir, 0777); err != nil {
return nil, err
}
if l == nil {
l = log.NewNopLogger()
}
if opts == nil {
opts = DefaultOptions
}
// Fixup bad format written by Prometheus 2.1.
if err := repairBadIndexVersion(l, dir); err != nil {
return nil, err
}
// Migrate old WAL.
if err := MigrateWAL(l, filepath.Join(dir, "wal")); err != nil {
return nil, errors.Wrap(err, "migrate WAL")
}
db = &DB{
dir: dir,
logger: l,
opts: opts,
compactc: make(chan struct{}, 1),
donec: make(chan struct{}),
stopc: make(chan struct{}),
compactionsEnabled: true,
chunkPool: chunkenc.NewPool(),
}
db.metrics = newDBMetrics(db, r)
if !opts.NoLockfile {
absdir, err := filepath.Abs(dir)
if err != nil {
return nil, err
}
lockf, _, err := fileutil.Flock(filepath.Join(absdir, "lock"))
if err != nil {
return nil, errors.Wrap(err, "lock DB directory")
}
db.lockf = lockf
}
db.compactor, err = NewLeveledCompactor(r, l, opts.BlockRanges, db.chunkPool)
if err != nil {
return nil, errors.Wrap(err, "create leveled compactor")
}
wlog, err := wal.New(l, r, filepath.Join(dir, "wal"))
if err != nil {
return nil, err
}
db.head, err = NewHead(r, l, wlog, opts.BlockRanges[0])
if err != nil {
return nil, err
}
if err := db.reload(); err != nil {
return nil, err
}
if err := db.head.Init(); err != nil {
return nil, errors.Wrap(err, "read WAL")
}
go db.run()
return db, nil
}
// Dir returns the directory of the database.
func (db *DB) Dir() string {
return db.dir
}
func (db *DB) run() {
defer close(db.donec)
backoff := time.Duration(0)
for {
select {
case <-db.stopc:
return
case <-time.After(backoff):
}
select {
case <-time.After(1 * time.Minute):
select {
case db.compactc <- struct{}{}:
default:
}
case <-db.compactc:
db.metrics.compactionsTriggered.Inc()
_, err := db.compact()
if err != nil {
level.Error(db.logger).Log("msg", "compaction failed", "err", err)
backoff = exponential(backoff, 1*time.Second, 1*time.Minute)
} else {
backoff = 0
}
case <-db.stopc:
return
}
}
}
func (db *DB) beyondRetention(meta *BlockMeta) bool {
if db.opts.RetentionDuration == 0 {
return false
}
db.mtx.RLock()
blocks := db.blocks[:]
db.mtx.RUnlock()
if len(blocks) == 0 {
return false
}
last := blocks[len(db.blocks)-1]
mint := last.Meta().MaxTime - int64(db.opts.RetentionDuration)
return meta.MaxTime < mint
}
// Appender opens a new appender against the database.
func (db *DB) Appender() Appender {
return dbAppender{db: db, Appender: db.head.Appender()}
}
// dbAppender wraps the DB's head appender and triggers compactions on commit
// if necessary.
type dbAppender struct {
Appender
db *DB
}
func (a dbAppender) Commit() error {
err := a.Appender.Commit()
// We could just run this check every few minutes practically. But for benchmarks
// and high frequency use cases this is the safer way.
if a.db.head.MaxTime()-a.db.head.MinTime() > a.db.head.chunkRange/2*3 {
select {
case a.db.compactc <- struct{}{}:
default:
}
}
return err
}
// Compact data if possible. After successful compaction blocks are reloaded
// which will also trigger blocks to be deleted that fall out of the retention
// window.
// If no blocks are compacted, the retention window state doesn't change. Thus,
// this is sufficient to reliably delete old data.
// Old blocks are only deleted on reload based on the new block's parent information.
// See DB.reload documentation for further information.
func (db *DB) compact() (changes bool, err error) {
db.cmtx.Lock()
defer db.cmtx.Unlock()
if !db.compactionsEnabled {
return false, nil
}
// Check whether we have pending head blocks that are ready to be persisted.
// They have the highest priority.
for {
select {
case <-db.stopc:
return changes, nil
default:
}
// The head has a compactable range if 1.5 level 0 ranges are between the oldest
// and newest timestamp. The 0.5 acts as a buffer of the appendable window.
if db.head.MaxTime()-db.head.MinTime() <= db.opts.BlockRanges[0]/2*3 {
break
}
mint, maxt := rangeForTimestamp(db.head.MinTime(), db.opts.BlockRanges[0])
// Wrap head into a range that bounds all reads to it.
head := &rangeHead{
head: db.head,
mint: mint,
// We remove 1 millisecond from maxt because block
// intervals are half-open: [b.MinTime, b.MaxTime). But
// chunk intervals are closed: [c.MinTime, c.MaxTime];
// so in order to make sure that overlaps are evaluated
// consistently, we explicitly remove the last value
// from the block interval here.
maxt: maxt - 1,
}
if _, err = db.compactor.Write(db.dir, head, mint, maxt, nil); err != nil {
return changes, errors.Wrap(err, "persist head block")
}
changes = true
runtime.GC()
if err := db.reload(); err != nil {
return changes, errors.Wrap(err, "reload blocks")
}
runtime.GC()
}
// Check for compactions of multiple blocks.
for {
plan, err := db.compactor.Plan(db.dir)
if err != nil {
return changes, errors.Wrap(err, "plan compaction")
}
if len(plan) == 0 {
break
}
select {
case <-db.stopc:
return changes, nil
default:
}
if _, err := db.compactor.Compact(db.dir, plan...); err != nil {
return changes, errors.Wrapf(err, "compact %s", plan)
}
changes = true
runtime.GC()
if err := db.reload(); err != nil {
return changes, errors.Wrap(err, "reload blocks")
}
runtime.GC()
}
return changes, nil
}
func (db *DB) getBlock(id ulid.ULID) (*Block, bool) {
for _, b := range db.blocks {
if b.Meta().ULID == id {
return b, true
}
}
return nil, false
}
// reload on-disk blocks and trigger head truncation if new blocks appeared. It takes
// a list of block directories which should be deleted during reload.
// Blocks that are obsolete due to replacement or retention will be deleted.
func (db *DB) reload() (err error) {
defer func() {
if err != nil {
db.metrics.reloadsFailed.Inc()
}
db.metrics.reloads.Inc()
}()
dirs, err := blockDirs(db.dir)
if err != nil {
return errors.Wrap(err, "find blocks")
}
// We delete old blocks that have been superseded by new ones by gathering all parents
// from existing blocks. Those parents all have newer replacements and can be safely deleted
// after we loaded the other blocks.
// This makes us resilient against the process crashing towards the end of a compaction.
// Creation of a new block and deletion of its parents cannot happen atomically. By creating
// blocks with their parents, we can pick up the deletion where it left off during a crash.
var (
blocks []*Block
corrupted = map[ulid.ULID]error{}
opened = map[ulid.ULID]struct{}{}
deleteable = map[ulid.ULID]struct{}{}
)
for _, dir := range dirs {
meta, err := readMetaFile(dir)
if err != nil {
// The block was potentially in the middle of being deleted during a crash.
// Skip it since we may delete it properly further down again.
level.Warn(db.logger).Log("msg", "read meta information", "err", err, "dir", dir)
ulid, err2 := ulid.Parse(filepath.Base(dir))
if err2 != nil {
level.Error(db.logger).Log("msg", "not a block dir", "dir", dir)
continue
}
corrupted[ulid] = err
continue
}
if db.beyondRetention(meta) {
deleteable[meta.ULID] = struct{}{}
continue
}
for _, b := range meta.Compaction.Parents {
deleteable[b.ULID] = struct{}{}
}
}
// Blocks we failed to open should all be those we are want to delete anyway.
for c, err := range corrupted {
if _, ok := deleteable[c]; !ok {
return errors.Wrapf(err, "unexpected corrupted block %s", c)
}
}
// Load new blocks into memory.
for _, dir := range dirs {
meta, err := readMetaFile(dir)
if err != nil {
return errors.Wrapf(err, "read meta information %s", dir)
}
// Don't load blocks that are scheduled for deletion.
if _, ok := deleteable[meta.ULID]; ok {
continue
}
// See if we already have the block in memory or open it otherwise.
b, ok := db.getBlock(meta.ULID)
if !ok {
b, err = OpenBlock(dir, db.chunkPool)
if err != nil {
return errors.Wrapf(err, "open block %s", dir)
}
}
blocks = append(blocks, b)
opened[meta.ULID] = struct{}{}
}
sort.Slice(blocks, func(i, j int) bool {
return blocks[i].Meta().MinTime < blocks[j].Meta().MinTime
})
if err := validateBlockSequence(blocks); err != nil {
return errors.Wrap(err, "invalid block sequence")
}
// Swap in new blocks first for subsequently created readers to be seen.
// Then close previous blocks, which may block for pending readers to complete.
db.mtx.Lock()
oldBlocks := db.blocks
db.blocks = blocks
db.mtx.Unlock()
// Drop old blocks from memory.
for _, b := range oldBlocks {
if _, ok := opened[b.Meta().ULID]; ok {
continue
}
if err := b.Close(); err != nil {
level.Warn(db.logger).Log("msg", "closing block failed", "err", err)
}
}
// Delete all obsolete blocks. None of them are opened any longer.
for ulid := range deleteable {
if err := os.RemoveAll(filepath.Join(db.dir, ulid.String())); err != nil {
return errors.Wrapf(err, "delete obsolete block %s", ulid)
}
}
// Garbage collect data in the head if the most recent persisted block
// covers data of its current time range.
if len(blocks) == 0 {
return nil
}
maxt := blocks[len(blocks)-1].Meta().MaxTime
return errors.Wrap(db.head.Truncate(maxt), "head truncate failed")
}
// validateBlockSequence returns error if given block meta files indicate that some blocks overlaps within sequence.
func validateBlockSequence(bs []*Block) error {
if len(bs) <= 1 {
return nil
}
var metas []BlockMeta
for _, b := range bs {
metas = append(metas, b.meta)
}
overlaps := OverlappingBlocks(metas)
if len(overlaps) > 0 {
return errors.Errorf("block time ranges overlap: %s", overlaps)
}
return nil
}
// TimeRange specifies minTime and maxTime range.
type TimeRange struct {
Min, Max int64
}
// Overlaps contains overlapping blocks aggregated by overlapping range.
type Overlaps map[TimeRange][]BlockMeta
// String returns human readable string form of overlapped blocks.
func (o Overlaps) String() string {
var res []string
for r, overlaps := range o {
var groups []string
for _, m := range overlaps {
groups = append(groups, fmt.Sprintf(
"<ulid: %s, mint: %d, maxt: %d, range: %s>",
m.ULID.String(),
m.MinTime,
m.MaxTime,
(time.Duration((m.MaxTime-m.MinTime)/1000)*time.Second).String(),
))
}
res = append(res, fmt.Sprintf(
"[mint: %d, maxt: %d, range: %s, blocks: %d]: %s",
r.Min, r.Max,
(time.Duration((r.Max-r.Min)/1000)*time.Second).String(),
len(overlaps),
strings.Join(groups, ", ")),
)
}
return strings.Join(res, "\n")
}
// OverlappingBlocks returns all overlapping blocks from given meta files.
func OverlappingBlocks(bm []BlockMeta) Overlaps {
if len(bm) <= 1 {
return nil
}
var (
overlaps [][]BlockMeta
// pending contains not ended blocks in regards to "current" timestamp.
pending = []BlockMeta{bm[0]}
// continuousPending helps to aggregate same overlaps to single group.
continuousPending = true
)
// We have here blocks sorted by minTime. We iterate over each block and treat its minTime as our "current" timestamp.
// We check if any of the pending block finished (blocks that we have seen before, but their maxTime was still ahead current
// timestamp). If not, it means they overlap with our current block. In the same time current block is assumed pending.
for _, b := range bm[1:] {
var newPending []BlockMeta
for _, p := range pending {
// "b.MinTime" is our current time.
if b.MinTime >= p.MaxTime {
continuousPending = false
continue
}
// "p" overlaps with "b" and "p" is still pending.
newPending = append(newPending, p)
}
// Our block "b" is now pending.
pending = append(newPending, b)
if len(newPending) == 0 {
// No overlaps.
continue
}
if continuousPending && len(overlaps) > 0 {
overlaps[len(overlaps)-1] = append(overlaps[len(overlaps)-1], b)
continue
}
overlaps = append(overlaps, append(newPending, b))
// Start new pendings.
continuousPending = true
}
// Fetch the critical overlapped time range foreach overlap groups.
overlapGroups := Overlaps{}
for _, overlap := range overlaps {
minRange := TimeRange{Min: 0, Max: math.MaxInt64}
for _, b := range overlap {
if minRange.Max > b.MaxTime {
minRange.Max = b.MaxTime
}
if minRange.Min < b.MinTime {
minRange.Min = b.MinTime
}
}
overlapGroups[minRange] = overlap
}
return overlapGroups
}
func (db *DB) String() string {
return "HEAD"
}
// Blocks returns the databases persisted blocks.
func (db *DB) Blocks() []*Block {
db.mtx.RLock()
defer db.mtx.RUnlock()
return db.blocks
}
// Head returns the databases's head.
func (db *DB) Head() *Head {
return db.head
}
// Close the partition.
func (db *DB) Close() error {
close(db.stopc)
<-db.donec
db.mtx.Lock()
defer db.mtx.Unlock()
var g errgroup.Group
// blocks also contains all head blocks.
for _, pb := range db.blocks {
g.Go(pb.Close)
}
var merr MultiError
merr.Add(g.Wait())
if db.lockf != nil {
merr.Add(db.lockf.Release())
}
merr.Add(db.head.Close())
return merr.Err()
}
// DisableCompactions disables compactions.
func (db *DB) DisableCompactions() {
db.cmtx.Lock()
defer db.cmtx.Unlock()
db.compactionsEnabled = false
level.Info(db.logger).Log("msg", "compactions disabled")
}
// EnableCompactions enables compactions.
func (db *DB) EnableCompactions() {
db.cmtx.Lock()
defer db.cmtx.Unlock()
db.compactionsEnabled = true
level.Info(db.logger).Log("msg", "compactions enabled")
}
// Snapshot writes the current data to the directory. If withHead is set to true it
// will create a new block containing all data that's currently in the memory buffer/WAL.
func (db *DB) Snapshot(dir string, withHead bool) error {
if dir == db.dir {
return errors.Errorf("cannot snapshot into base directory")
}
if _, err := ulid.Parse(dir); err == nil {
return errors.Errorf("dir must not be a valid ULID")
}
db.cmtx.Lock()
defer db.cmtx.Unlock()
db.mtx.RLock()
defer db.mtx.RUnlock()
for _, b := range db.blocks {
level.Info(db.logger).Log("msg", "snapshotting block", "block", b)
if err := b.Snapshot(dir); err != nil {
return errors.Wrapf(err, "error snapshotting block: %s", b.Dir())
}
}
if !withHead {
return nil
}
_, err := db.compactor.Write(dir, db.head, db.head.MinTime(), db.head.MaxTime(), nil)
return errors.Wrap(err, "snapshot head block")
}
// Querier returns a new querier over the data partition for the given time range.
// A goroutine must not handle more than one open Querier.
func (db *DB) Querier(mint, maxt int64) (Querier, error) {
var blocks []BlockReader
db.mtx.RLock()
defer db.mtx.RUnlock()
for _, b := range db.blocks {
if b.OverlapsClosedInterval(mint, maxt) {
blocks = append(blocks, b)
}
}
if maxt >= db.head.MinTime() {
blocks = append(blocks, db.head)
}
sq := &querier{
blocks: make([]Querier, 0, len(blocks)),
}
for _, b := range blocks {
q, err := NewBlockQuerier(b, mint, maxt)
if err == nil {
sq.blocks = append(sq.blocks, q)
continue
}
// If we fail, all previously opened queriers must be closed.
for _, q := range sq.blocks {
q.Close()
}
return nil, errors.Wrapf(err, "open querier for block %s", b)
}
return sq, nil
}
func rangeForTimestamp(t int64, width int64) (mint, maxt int64) {
mint = (t / width) * width
return mint, mint + width
}
// Delete implements deletion of metrics. It only has atomicity guarantees on a per-block basis.
func (db *DB) Delete(mint, maxt int64, ms ...labels.Matcher) error {
db.cmtx.Lock()
defer db.cmtx.Unlock()
var g errgroup.Group
db.mtx.RLock()
defer db.mtx.RUnlock()
for _, b := range db.blocks {
if b.OverlapsClosedInterval(mint, maxt) {
g.Go(func(b *Block) func() error {
return func() error { return b.Delete(mint, maxt, ms...) }
}(b))
}
}
g.Go(func() error {
return db.head.Delete(mint, maxt, ms...)
})
return g.Wait()
}
// CleanTombstones re-writes any blocks with tombstones.
func (db *DB) CleanTombstones() (err error) {
db.cmtx.Lock()
defer db.cmtx.Unlock()
start := time.Now()
defer db.metrics.tombCleanTimer.Observe(time.Since(start).Seconds())
newUIDs := []ulid.ULID{}
defer func() {
// If any error is caused, we need to delete all the new directory created.
if err != nil {
for _, uid := range newUIDs {
dir := filepath.Join(db.Dir(), uid.String())
if err := os.RemoveAll(dir); err != nil {
level.Error(db.logger).Log("msg", "failed to delete block after failed `CleanTombstones`", "dir", dir, "err", err)
}
}
}
}()
db.mtx.RLock()
blocks := db.blocks[:]
db.mtx.RUnlock()
for _, b := range blocks {
if uid, er := b.CleanTombstones(db.Dir(), db.compactor); er != nil {
err = errors.Wrapf(er, "clean tombstones: %s", b.Dir())
return err
} else if uid != nil { // New block was created.
newUIDs = append(newUIDs, *uid)
}
}
return errors.Wrap(db.reload(), "reload blocks")
}
func isBlockDir(fi os.FileInfo) bool {
if !fi.IsDir() {
return false
}
_, err := ulid.Parse(fi.Name())
return err == nil
}
func blockDirs(dir string) ([]string, error) {
files, err := ioutil.ReadDir(dir)
if err != nil {
return nil, err
}
var dirs []string
for _, fi := range files {
if isBlockDir(fi) {
dirs = append(dirs, filepath.Join(dir, fi.Name()))
}
}
return dirs, nil
}
func sequenceFiles(dir string) ([]string, error) {
files, err := ioutil.ReadDir(dir)
if err != nil {
return nil, err
}
var res []string
for _, fi := range files {
if _, err := strconv.ParseUint(fi.Name(), 10, 64); err != nil {
continue
}
res = append(res, filepath.Join(dir, fi.Name()))
}
return res, nil
}
func nextSequenceFile(dir string) (string, int, error) {
names, err := fileutil.ReadDir(dir)
if err != nil {
return "", 0, err
}
i := uint64(0)
for _, n := range names {
j, err := strconv.ParseUint(n, 10, 64)
if err != nil {
continue
}
i = j
}
return filepath.Join(dir, fmt.Sprintf("%0.6d", i+1)), int(i + 1), nil
}
// The MultiError type implements the error interface, and contains the
// Errors used to construct it.
type MultiError []error
// Returns a concatenated string of the contained errors
func (es MultiError) Error() string {
var buf bytes.Buffer
if len(es) > 1 {
fmt.Fprintf(&buf, "%d errors: ", len(es))
}
for i, err := range es {
if i != 0 {
buf.WriteString("; ")
}
buf.WriteString(err.Error())
}
return buf.String()
}
// Add adds the error to the error list if it is not nil.
func (es *MultiError) Add(err error) {
if err == nil {
return
}
if merr, ok := err.(MultiError); ok {
*es = append(*es, merr...)
} else {
*es = append(*es, err)
}
}
// Err returns the error list as an error or nil if it is empty.
func (es MultiError) Err() error {
if len(es) == 0 {
return nil
}
return es
}
func closeAll(cs ...io.Closer) error {
var merr MultiError
for _, c := range cs {
merr.Add(c.Close())
}
return merr.Err()
}
func exponential(d, min, max time.Duration) time.Duration {
d *= 2
if d < min {
d = min
}
if d > max {
d = max
}
return d
}