server, sql: collect additional session details

Partially addresses cockroachdb#74257.

Previously, the sql server did not provide additional session details
such as total number of transactions executed, transaction fingerprint
IDs, and total active time. This change adds the aforementioned session
details to the `serverpb.Session` struct.

To track transaction fingerprint IDs, a new circular buffer
`TxnFingerprintIDBuffer` is introduced with its corresponding cluster
setting `TxnFingerprintIDBufferCapacity` which controls the capacity.
The total number of transactions executed is accumulated using the `txnCounter`
from the `extraTxnState` in `connExecutor`. The total active time is calculated
by a `timeutil.StopWatch` which is started and stopped when a transaction is
started, restarted, and finished.

Release note (api change): the `serverpb.Session` struct now has three
new fields: number of transactions executed, transaction fingerprint
IDs, and total active time.

docs/generated/http/full.md

@@ -2108,9 +2108,12 @@ Session represents one SQL session.
 | alloc_bytes | [int64](#cockroach.server.serverpb.ListSessionsResponse-int64) |  | Number of currently allocated bytes in the session memory monitor. | [reserved](#support-status) |
 | max_alloc_bytes | [int64](#cockroach.server.serverpb.ListSessionsResponse-int64) |  | High water mark of allocated bytes in the session memory monitor. | [reserved](#support-status) |
 | active_txn | [TxnInfo](#cockroach.server.serverpb.ListSessionsResponse-cockroach.server.serverpb.TxnInfo) |  | Information about the txn in progress on this session. Nil if the session doesn't currently have a transaction. | [reserved](#support-status) |
+| num_txns_executed | [int32](#cockroach.server.serverpb.ListSessionsResponse-int32) |  | Number of transactions that were executed so far on this session. | [reserved](#support-status) |
+| txnFingerprintIDs | [uint64](#cockroach.server.serverpb.ListSessionsResponse-uint64) | repeated | List of transaction fingerprint IDs in this session. | [reserved](#support-status) |
 | last_active_query_no_constants | [string](#cockroach.server.serverpb.ListSessionsResponse-string) |  | The SQL statement fingerprint of the last query executed on this session, compatible with StatementStatisticsKey. | [reserved](#support-status) |
 | status | [Session.Status](#cockroach.server.serverpb.ListSessionsResponse-cockroach.server.serverpb.Session.Status) |  | The session's status. | [reserved](#support-status) |
 | end | [google.protobuf.Timestamp](#cockroach.server.serverpb.ListSessionsResponse-google.protobuf.Timestamp) |  | Timestamp of session's end. | [reserved](#support-status) |
+| totalActiveTime | [google.protobuf.Duration](#cockroach.server.serverpb.ListSessionsResponse-google.protobuf.Duration) |  | The session's total active time. | [reserved](#support-status) |
 
 
 
@@ -2242,9 +2245,12 @@ Session represents one SQL session.
 | alloc_bytes | [int64](#cockroach.server.serverpb.ListSessionsResponse-int64) |  | Number of currently allocated bytes in the session memory monitor. | [reserved](#support-status) |
 | max_alloc_bytes | [int64](#cockroach.server.serverpb.ListSessionsResponse-int64) |  | High water mark of allocated bytes in the session memory monitor. | [reserved](#support-status) |
 | active_txn | [TxnInfo](#cockroach.server.serverpb.ListSessionsResponse-cockroach.server.serverpb.TxnInfo) |  | Information about the txn in progress on this session. Nil if the session doesn't currently have a transaction. | [reserved](#support-status) |
+| num_txns_executed | [int32](#cockroach.server.serverpb.ListSessionsResponse-int32) |  | Number of transactions that were executed so far on this session. | [reserved](#support-status) |
+| txnFingerprintIDs | [uint64](#cockroach.server.serverpb.ListSessionsResponse-uint64) | repeated | List of transaction fingerprint IDs in this session. | [reserved](#support-status) |
 | last_active_query_no_constants | [string](#cockroach.server.serverpb.ListSessionsResponse-string) |  | The SQL statement fingerprint of the last query executed on this session, compatible with StatementStatisticsKey. | [reserved](#support-status) |
 | status | [Session.Status](#cockroach.server.serverpb.ListSessionsResponse-cockroach.server.serverpb.Session.Status) |  | The session's status. | [reserved](#support-status) |
 | end | [google.protobuf.Timestamp](#cockroach.server.serverpb.ListSessionsResponse-google.protobuf.Timestamp) |  | Timestamp of session's end. | [reserved](#support-status) |
+| totalActiveTime | [google.protobuf.Duration](#cockroach.server.serverpb.ListSessionsResponse-google.protobuf.Duration) |  | The session's total active time. | [reserved](#support-status) |
 
 
 

docs/generated/settings/settings-for-tenants.txt

@@ -186,6 +186,7 @@ sql.ttl.default_range_concurrency	integer	1	default amount of ranges to process
 sql.ttl.default_select_batch_size	integer	500	default amount of rows to select in a single query during a TTL job
 sql.ttl.job.enabled	boolean	true	whether the TTL job is enabled
 sql.ttl.range_batch_size	integer	100	amount of ranges to fetch at a time for a table during the TTL job
+sql.txn_fingerprint_id_buffer.capacity	integer	100	the maximum number of txn fingerprint IDs stored
 timeseries.storage.enabled	boolean	true	if set, periodic timeseries data is stored within the cluster; disabling is not recommended unless you are storing the data elsewhere
 timeseries.storage.resolution_10s.ttl	duration	240h0m0s	the maximum age of time series data stored at the 10 second resolution. Data older than this is subject to rollup and deletion.
 timeseries.storage.resolution_30m.ttl	duration	2160h0m0s	the maximum age of time series data stored at the 30 minute resolution. Data older than this is subject to deletion.

docs/generated/settings/settings.html

@@ -202,6 +202,7 @@
 <tr><td><code>sql.ttl.default_select_batch_size</code></td><td>integer</td><td><code>500</code></td><td>default amount of rows to select in a single query during a TTL job</td></tr>
 <tr><td><code>sql.ttl.job.enabled</code></td><td>boolean</td><td><code>true</code></td><td>whether the TTL job is enabled</td></tr>
 <tr><td><code>sql.ttl.range_batch_size</code></td><td>integer</td><td><code>100</code></td><td>amount of ranges to fetch at a time for a table during the TTL job</td></tr>
+<tr><td><code>sql.txn_fingerprint_id_buffer.capacity</code></td><td>integer</td><td><code>100</code></td><td>the maximum number of txn fingerprint IDs stored</td></tr>
 <tr><td><code>timeseries.storage.enabled</code></td><td>boolean</td><td><code>true</code></td><td>if set, periodic timeseries data is stored within the cluster; disabling is not recommended unless you are storing the data elsewhere</td></tr>
 <tr><td><code>timeseries.storage.resolution_10s.ttl</code></td><td>duration</td><td><code>240h0m0s</code></td><td>the maximum age of time series data stored at the 10 second resolution. Data older than this is subject to rollup and deletion.</td></tr>
 <tr><td><code>timeseries.storage.resolution_30m.ttl</code></td><td>duration</td><td><code>2160h0m0s</code></td><td>the maximum age of time series data stored at the 30 minute resolution. Data older than this is subject to deletion.</td></tr>

docs/generated/swagger/spec.json

@@ -768,6 +768,12 @@
       },
       "x-go-package": "github.com/cockroachdb/cockroach/pkg/server/serverpb"
     },
+    "Duration": {
+      "description": "A Duration represents the elapsed time between two instants\nas an int64 nanosecond count. The representation limits the\nlargest representable duration to approximately 290 years.",
+      "type": "integer",
+      "format": "int64",
+      "x-go-package": "time"
+    },
     "EventsResponse": {
       "description": "EventsResponse contains a set of event log entries. This is always limited\nto the latest N entries (N is enforced in the associated endpoint).",
       "type": "object",
@@ -1220,6 +1226,12 @@
         "node_id": {
           "$ref": "#/definitions/NodeID"
         },
+        "num_txns_executed": {
+          "description": "Number of transactions that were executed so far on this session.",
+          "type": "integer",
+          "format": "int32",
+          "x-go-name": "NumTxnsExecuted"
+        },
         "start": {
           "description": "Timestamp of session's start.",
           "type": "string",
@@ -1229,6 +1241,17 @@
         "status": {
           "$ref": "#/definitions/Session_Status"
         },
+        "totalActiveTime": {
+          "$ref": "#/definitions/Duration"
+        },
+        "txnFingerprintIDs": {
+          "description": "List of transaction fingerprint IDs in this session.",
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/TransactionFingerprintID"
+          },
+          "x-go-name": "TxnFingerprintIDs"
+        },
         "username": {
           "description": "Username of the user for this session.",
           "type": "string",
@@ -1493,6 +1516,12 @@
       },
       "x-go-package": "github.com/cockroachdb/cockroach/pkg/util/hlc"
     },
+    "TransactionFingerprintID": {
+      "description": "TransactionFingerprintID is the hashed string constructed using the\nindividual statement fingerprint IDs that comprise the transaction.",
+      "type": "integer",
+      "format": "uint64",
+      "x-go-package": "github.com/cockroachdb/cockroach/pkg/roachpb"
+    },
     "TxnInfo": {
       "type": "object",
       "title": "TxnInfo represents an in flight user transaction on some Session.",

pkg/ccl/logictestccl/testdata/logic_test/crdb_internal_tenant

@@ -243,15 +243,15 @@ SELECT  * FROM crdb_internal.cluster_transactions WHERE node_id < 0
 ----
 id  node_id  session_id  start  txn_string  application_name  num_stmts  num_retries  num_auto_retries
 
-query ITTTTTTTTTTTTT colnames
+query ITTTTTTTTTTTTTT colnames
 SELECT * FROM crdb_internal.node_sessions WHERE node_id < 0
 ----
-node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
+node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  num_txns_executed  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
 
-query ITTTTTTTTTTTTT colnames
+query ITTTTTTTTTTTTTT colnames
 SELECT * FROM crdb_internal.cluster_sessions WHERE node_id < 0
 ----
-node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
+node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  num_txns_executed  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
 
 query IIITTTI colnames
 SELECT * FROM crdb_internal.node_contention_events WHERE table_id < 0

pkg/server/serverpb/status.proto

@@ -944,6 +944,12 @@ message Session {
   // Information about the txn in progress on this session. Nil if the
   // session doesn't currently have a transaction.
   TxnInfo active_txn = 12;
+  // Number of transactions that were executed so far on this session.
+  int32 num_txns_executed = 16;
+  // List of transaction fingerprint IDs in this session.
+  repeated uint64 txnFingerprintIDs = 17 [(gogoproto.customname) = "TxnFingerprintIDs",
+    (gogoproto.customtype) = "github.com/cockroachdb/cockroach/pkg/roachpb.TransactionFingerprintID",
+    (gogoproto.nullable) = false];
   // The SQL statement fingerprint of the last query executed on this session,
   // compatible with StatementStatisticsKey.
   string last_active_query_no_constants = 13;
@@ -958,6 +964,9 @@ message Session {
   // Timestamp of session's end.
   google.protobuf.Timestamp end = 15
       [ (gogoproto.nullable) = true, (gogoproto.stdtime) = true ];
+  // The session's total active time.
+  google.protobuf.Duration totalActiveTime = 18 [(gogoproto.nullable) = false,
+    (gogoproto.stdduration) = true];
 }
 
 // An error wrapper object for ListSessionsResponse.

pkg/sql/BUILD.bazel

@@ -223,6 +223,7 @@ go_library(
         "topk.go",
         "truncate.go",
         "txn_state.go",
+        "txn_fingerprint_id_buffer.go",
         "type_change.go",
         "unary.go",
         "union.go",

pkg/sql/conn_executor.go

@@ -883,6 +883,8 @@ func (s *Server) newConnExecutor(
 		stmtDiagnosticsRecorder:   s.cfg.StmtDiagnosticsRecorder,
 		indexUsageStats:           s.indexUsageStats,
 		txnIDCacheWriter:          s.txnIDCache,
+		totalActiveTimeStopWatch:  timeutil.NewStopWatch(),
+		txnFingerprintIDBuffer:    NewTxnFingerprintIDBuffer(s.cfg.Settings, s.cfg.RootMemoryMonitor),
 	}
 
 	ex.state.txnAbortCount = ex.metrics.EngineMetrics.TxnAbortCount
@@ -1497,6 +1499,13 @@ type connExecutor struct {
 	// txnIDCacheWriter is used to write txnidcache.ResolvedTxnID to the
 	// Transaction ID Cache.
 	txnIDCacheWriter txnidcache.Writer
+
+	// txnFingerprintIDBuffer is a circular buffer keeping track of the
+	// txnFingerprintIDs in this session.
+	txnFingerprintIDBuffer *TxnFingerprintIDBuffer
+
+	// totalActiveTimeStopWatch tracks the total active time of the session.
+	totalActiveTimeStopWatch *timeutil.StopWatch
 }
 
 // ctxHolder contains a connection's context and, while session tracing is
@@ -3115,19 +3124,24 @@ func (ex *connExecutor) serialize() serverpb.Session {
 		remoteStr = sd.RemoteAddr.String()
 	}
 
+	txnFingerprintIDs := ex.txnFingerprintIDBuffer.GetAllTxnFingerprintIDs()
+
 	return serverpb.Session{
 		Username:                   sd.SessionUser().Normalized(),
 		ClientAddress:              remoteStr,
 		ApplicationName:            ex.applicationName.Load().(string),
 		Start:                      ex.phaseTimes.GetSessionPhaseTime(sessionphase.SessionInit).UTC(),
 		ActiveQueries:              activeQueries,
 		ActiveTxn:                  activeTxnInfo,
+		NumTxnsExecuted:            int32(ex.extraTxnState.txnCounter),
+		TxnFingerprintIDs:          txnFingerprintIDs,
 		LastActiveQuery:            lastActiveQuery,
 		ID:                         ex.sessionID.GetBytes(),
 		AllocBytes:                 ex.mon.AllocBytes(),
 		MaxAllocBytes:              ex.mon.MaximumBytes(),
 		LastActiveQueryNoConstants: lastActiveQueryNoConstants,
 		Status:                     status,
+		TotalActiveTime:            ex.totalActiveTimeStopWatch.Elapsed(),
 	}
 }
 

pkg/sql/conn_executor_exec.go

@@ -2101,6 +2101,12 @@ func (ex *connExecutor) onTxnFinish(ctx context.Context, ev txnEvent) {
 		ex.phaseTimes.SetSessionPhaseTime(sessionphase.SessionEndExecTransaction, timeutil.Now())
 		transactionFingerprintID :=
 			roachpb.TransactionFingerprintID(ex.extraTxnState.transactionStatementsHash.Sum())
+		err := ex.txnFingerprintIDBuffer.Enqueue(transactionFingerprintID)
+		if err != nil {
+			if log.V(1) {
+				log.Warningf(ctx, "failed to enqueue transactionFingerprintID = %d: %s", transactionFingerprintID, err)
+			}
+		}
 		if !implicit {
 			ex.statsCollector.EndExplicitTransaction(
 				ctx,
@@ -2114,7 +2120,7 @@ func (ex *connExecutor) onTxnFinish(ctx context.Context, ev txnEvent) {
 				transactionFingerprintID,
 			)
 		}
-		err := ex.recordTransactionFinish(ctx, transactionFingerprintID, ev, implicit, txnStart)
+		err = ex.recordTransactionFinish(ctx, transactionFingerprintID, ev, implicit, txnStart)
 		if err != nil {
 			if log.V(1) {
 				log.Warningf(ctx, "failed to record transaction stats: %s", err)
@@ -2126,6 +2132,8 @@ func (ex *connExecutor) onTxnFinish(ctx context.Context, ev txnEvent) {
 
 func (ex *connExecutor) onTxnRestart(ctx context.Context) {
 	if ex.extraTxnState.shouldExecuteOnTxnRestart {
+		ex.totalActiveTimeStopWatch.Stop()
+		defer ex.totalActiveTimeStopWatch.Start()
 		ex.phaseTimes.SetSessionPhaseTime(sessionphase.SessionMostRecentStartExecTransaction, timeutil.Now())
 		ex.extraTxnState.transactionStatementFingerprintIDs = nil
 		ex.extraTxnState.transactionStatementsHash = util.MakeFNV64()
@@ -2157,6 +2165,8 @@ func (ex *connExecutor) recordTransactionStart(txnID uuid.UUID) {
 	ex.state.mu.RUnlock()
 	implicit := ex.implicitTxn()
 
+	ex.totalActiveTimeStopWatch.Start()
+
 	// Transaction received time is the time at which the statement that prompted
 	// the creation of this transaction was received.
 	ex.phaseTimes.SetSessionPhaseTime(sessionphase.SessionTransactionReceived,
@@ -2210,6 +2220,7 @@ func (ex *connExecutor) recordTransactionFinish(
 
 	txnEnd := timeutil.Now()
 	txnTime := txnEnd.Sub(txnStart)
+	ex.totalActiveTimeStopWatch.Stop()
 	if ex.executorType != executorTypeInternal {
 		ex.metrics.EngineMetrics.SQLTxnsOpen.Dec(1)
 	}

pkg/sql/crdb_internal.go

@@ -1615,7 +1615,7 @@ CREATE TABLE crdb_internal.%s (
   node_id INT,             -- the ID of the node running the transaction
   session_id STRING,       -- the ID of the session
   start TIMESTAMP,         -- the start time of the transaction
-  txn_string STRING,       -- the string representation of the transcation
+  txn_string STRING,       -- the string representation of the transaction
   application_name STRING, -- the name of the application as per SET application_name
   num_stmts INT,           -- the number of statements executed so far
   num_retries INT,         -- the number of times the transaction was restarted
@@ -1894,6 +1894,7 @@ CREATE TABLE crdb_internal.%s (
   application_name   STRING,         -- the name of the application as per SET application_name
   active_queries     STRING,         -- the currently running queries as SQL
   last_active_query  STRING,         -- the query that finished last on this session as SQL
+  num_txns_executed  INT,            -- the number of transactions that were executed so far on this session
   session_start      TIMESTAMP,      -- the time when the session was opened
   oldest_query_start TIMESTAMP,      -- the time when the oldest query in the session was started
   kv_txn             STRING,         -- the ID of the current KV transaction
@@ -1995,6 +1996,7 @@ func populateSessionsTable(
 			tree.NewDString(session.ApplicationName),
 			tree.NewDString(activeQueries.String()),
 			tree.NewDString(session.LastActiveQuery),
+			tree.NewDInt(tree.DInt(session.NumTxnsExecuted)),
 			startTSDatum,
 			oldestStartDatum,
 			kvTxnIDDatum,
@@ -2020,6 +2022,7 @@ func populateSessionsTable(
 				tree.DNull,                             // application name
 				tree.NewDString("-- "+rpcErr.Message),  // active queries
 				tree.DNull,                             // last active query
+				tree.DNull,                             // num txns executed
 				tree.DNull,                             // session start
 				tree.DNull,                             // oldest_query_start
 				tree.DNull,                             // kv_txn

pkg/sql/delegate/show_sessions.go

@@ -16,7 +16,7 @@ import (
 )
 
 func (d *delegator) delegateShowSessions(n *tree.ShowSessions) (tree.Statement, error) {
-	const query = `SELECT node_id, session_id, status, user_name, client_address, application_name, active_queries, last_active_query, session_start, oldest_query_start FROM crdb_internal.`
+	const query = `SELECT node_id, session_id, status, user_name, client_address, application_name, active_queries, last_active_query, num_txns_executed, session_start, oldest_query_start FROM crdb_internal.`
 	table := `node_sessions`
 	if n.Cluster {
 		table = `cluster_sessions`

pkg/sql/logictest/testdata/logic_test/crdb_internal

@@ -364,15 +364,15 @@ SELECT  * FROM crdb_internal.cluster_transactions WHERE node_id < 0
 ----
 id  node_id  session_id  start  txn_string  application_name  num_stmts  num_retries  num_auto_retries
 
-query ITTTTTTTTTTTTT colnames
+query ITTTTTTTTTTTTTT colnames
 SELECT * FROM crdb_internal.node_sessions WHERE node_id < 0
 ----
-node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
+node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  num_txns_executed  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
 
-query ITTTTTTTTTTTTT colnames
+query ITTTTTTTTTTTTTT colnames
 SELECT * FROM crdb_internal.cluster_sessions WHERE node_id < 0
 ----
-node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
+node_id  session_id  user_name  client_address  application_name  active_queries  last_active_query  num_txns_executed  session_start  oldest_query_start  kv_txn  alloc_bytes  max_alloc_bytes status session_end
 
 query IIITTTI colnames
 SELECT * FROM crdb_internal.node_contention_events WHERE table_id < 0