Merge #62164

62164: sql: remove vectorize_row_count_threshold setting r=yuzefovich a=yuzefovich

This commit removes `vectorize_row_count_threshold` session variable and
the corresponding cluster setting. In 21.1 release these are set to 0 by
default, and in 21.2 release that default behavior cannot be changed.
This marks another step towards the start of deprecating the row-by-row
execution engine.

Fixes: #53893.

Release note (sql change): `sql.defaults.vectorize_row_count_threshold`
cluster setting as well as corresponding `vectorize_row_count_threshold`
session variable have been removed. From now on, CockroachDB will behave
exactly as if these were set to 0 (last default value).

Co-authored-by: Yahor Yuzefovich <yahor@cockroachlabs.com>

pkg/ccl/changefeedccl/helpers_test.go

@@ -271,7 +271,6 @@ func sinklessTest(testFn func(*testing.T, *gosql.DB, cdctest.TestFeedFactory)) f
  // order to ensure that changefeeds work as expected with them (note
  // that we'll still use the row-by-row engine, see #55605).
  sqlDB.Exec(t, `SET CLUSTER SETTING sql.defaults.vectorize=on`)
- sqlDB.Exec(t, `SET CLUSTER SETTING sql.defaults.vectorize_row_count_threshold=0`)
  sqlDB.Exec(t, `CREATE DATABASE d`)
 
  sink, cleanup := sqlutils.PGUrl(t, s.ServingSQLAddr(), t.Name(), url.User(security.RootUser))

pkg/ccl/importccl/exportcsv_test.go

@@ -408,7 +408,6 @@ func TestExportVectorized(t *testing.T) {
  sqlDB := sqlutils.MakeSQLRunner(db)
 
  sqlDB.Exec(t, `CREATE TABLE t(a INT PRIMARY KEY)`)
- sqlDB.Exec(t, `SET vectorize_row_count_threshold=0`)
  sqlDB.Exec(t, `EXPORT INTO CSV 'http://0.1:37957/exp_1' FROM TABLE t`)
 }
 

pkg/cmd/roachtest/tpc_utils.go

@@ -110,15 +110,3 @@ func createStatsFromTables(t *test, conn *gosql.DB, tableNames []string) {
  }
  }
 }
-
-// disableVectorizeRowCountThresholdHeuristic sets
-// 'vectorize_row_count_threshold' cluster setting to zero so that the test
-// would use the vectorized engine with 'vectorize=on' regardless of the
-// fact whether the stats are present or not (if we don't set it, then when
-// the stats are not present, we fallback to row-by-row engine even with
-// `vectorize=on` set).
-func disableVectorizeRowCountThresholdHeuristic(t *test, conn *gosql.DB) {
- if _, err := conn.Exec("SET CLUSTER SETTING sql.defaults.vectorize_row_count_threshold=0"); err != nil {
- t.Fatal(err)
- }
-}

pkg/cmd/roachtest/tpcdsvec.go

@@ -57,7 +57,6 @@ func registerTPCDSVec(r *testRegistry) {
 
  clusterConn := c.Conn(ctx, 1)
  disableAutoStats(t, clusterConn)
- disableVectorizeRowCountThresholdHeuristic(t, clusterConn)
  t.Status("restoring TPCDS dataset for Scale Factor 1")
  if _, err := clusterConn.Exec(
  `RESTORE DATABASE tpcds FROM 'gs://cockroach-fixtures/workload/tpcds/scalefactor=1/backup';`,

pkg/cmd/roachtest/tpchvec.go

@@ -617,7 +617,6 @@ func runTPCHVec(
 
  conn := c.Conn(ctx, 1)
  disableAutoStats(t, conn)
- disableVectorizeRowCountThresholdHeuristic(t, conn)
  t.Status("restoring TPCH dataset for Scale Factor 1")
  if err := loadTPCHDataset(ctx, t, c, 1 /* sf */, newMonitor(ctx, c), c.All()); err != nil {
  t.Fatal(err)

pkg/settings/registry.go

@@ -77,6 +77,8 @@ var retiredSettings = map[string]struct{}{
  "sql.testing.mutations.max_batch_size": {},
  "sql.testing.mock_contention.enabled": {},
  "kv.atomic_replication_changes.enabled": {},
+ // removed as of 21.2.
+ "sql.defaults.vectorize_row_count_threshold": {},
 }
 
 // register adds a setting to the registry.

pkg/sql/BUILD.bazel

@@ -283,7 +283,6 @@ go_library(
  "//pkg/sql/catalog/schemaexpr",
  "//pkg/sql/catalog/tabledesc",
  "//pkg/sql/catalog/typedesc",
- "//pkg/sql/colexec",
  "//pkg/sql/colflow",
  "//pkg/sql/contention",
  "//pkg/sql/covering",

pkg/sql/colexec/constants.go

@@ -10,12 +10,6 @@
 
 package colexec
 
-// DefaultVectorizeRowCountThreshold denotes the default row count threshold.
-// When it is met, the vectorized execution engine will be used if possible.
-// TODO(yuzefovich): remove this together with vectorize_row_count_threshold
-// setting.
-const DefaultVectorizeRowCountThreshold = 0
-
 // VecMaxOpenFDsLimit specifies the maximum number of open file descriptors
 // that the vectorized engine can have (globally) for use of the temporary
 // storage.

pkg/sql/distsql_physical_planner.go

@@ -1323,9 +1323,6 @@ func (dsp *DistSQLPlanner) planTableReaders(
 
  tr.Parallelize = info.parallelize
  p.TotalEstimatedScannedRows += info.estimatedRowCount
- if info.estimatedRowCount > p.MaxEstimatedRowCount {
- p.MaxEstimatedRowCount = info.estimatedRowCount
- }
 
  corePlacement[i].NodeID = sp.Node
  corePlacement[i].Core.TableReader = tr

pkg/sql/distsql_running.go

@@ -126,7 +126,6 @@ func (dsp *DistSQLPlanner) setupFlows(
  flows map[roachpb.NodeID]*execinfrapb.FlowSpec,
  recv *DistSQLReceiver,
  localState distsql.LocalState,
- vectorizeThresholdMet bool,
  collectStats bool,
 ) (context.Context, flowinfra.Flow, error) {
  thisNodeID := dsp.gatewayNodeID
@@ -155,26 +154,18 @@ func (dsp *DistSQLPlanner) setupFlows(
  }
 
  if vectorizeMode := evalCtx.SessionData.VectorizeMode; vectorizeMode != sessiondatapb.VectorizeOff {
- if !vectorizeThresholdMet && vectorizeMode == sessiondatapb.VectorizeOn {
- // Vectorization is not justified for this flow because the expected
- // amount of data is too small and the overhead of pre-allocating data
- // structures needed for the vectorized engine is expected to dominate
- // the execution time.
- setupReq.EvalContext.SessionData.VectorizeMode = sessiondatapb.VectorizeOff
- } else {
- // Now we determine whether the vectorized engine supports the flow
- // specs.
- for _, spec := range flows {
- if err := colflow.IsSupported(vectorizeMode, spec); err != nil {
- log.VEventf(ctx, 1, "failed to vectorize: %s", err)
- if vectorizeMode == sessiondatapb.VectorizeExperimentalAlways {
- return nil, nil, err
- }
- // Vectorization is not supported for this flow, so we override the
- // setting.
- setupReq.EvalContext.SessionData.VectorizeMode = sessiondatapb.VectorizeOff
- break
+ // Now we determine whether the vectorized engine supports the flow
+ // specs.
+ for _, spec := range flows {
+ if err := colflow.IsSupported(vectorizeMode, spec); err != nil {
+ log.VEventf(ctx, 1, "failed to vectorize: %s", err)
+ if vectorizeMode == sessiondatapb.VectorizeExperimentalAlways {
+ return nil, nil, err
  }
+ // Vectorization is not supported for this flow, so we override the
+ // setting.
+ setupReq.EvalContext.SessionData.VectorizeMode = sessiondatapb.VectorizeOff
+ break
  }
  }
  }
@@ -325,16 +316,14 @@ func (dsp *DistSQLPlanner) Run(
  recv.outputTypes = plan.GetResultTypes()
  recv.contendedQueryMetric = dsp.distSQLSrv.Metrics.ContendedQueriesCount
 
- vectorizedThresholdMet := plan.MaxEstimatedRowCount >= evalCtx.SessionData.VectorizeRowCountThreshold
-
  if len(flows) == 1 {
  // We ended up planning everything locally, regardless of whether we
  // intended to distribute or not.
  localState.IsLocal = true
  }
 
  ctx, flow, err := dsp.setupFlows(
- ctx, evalCtx, leafInputState, flows, recv, localState, vectorizedThresholdMet, planCtx.collectExecStats,
+ ctx, evalCtx, leafInputState, flows, recv, localState, planCtx.collectExecStats,
  )
  if err != nil {
  recv.SetError(err)

pkg/sql/exec_util.go

@@ -50,7 +50,6 @@ import (
  "github.com/cockroachdb/cockroach/pkg/sql/catalog/descs"
  "github.com/cockroachdb/cockroach/pkg/sql/catalog/hydratedtables"
  "github.com/cockroachdb/cockroach/pkg/sql/catalog/lease"
- "github.com/cockroachdb/cockroach/pkg/sql/colexec"
  "github.com/cockroachdb/cockroach/pkg/sql/contention"
  "github.com/cockroachdb/cockroach/pkg/sql/distsql"
  "github.com/cockroachdb/cockroach/pkg/sql/execinfra"
@@ -422,22 +421,6 @@ var VectorizeClusterMode = settings.RegisterEnumSetting(
  },
 )
 
-// VectorizeRowCountThresholdClusterValue controls the cluster default for the
-// vectorize row count threshold. When it is met, the vectorized execution
-// engine will be used if possible.
-var VectorizeRowCountThresholdClusterValue = settings.RegisterIntSetting(
- "sql.defaults.vectorize_row_count_threshold",
- "default vectorize row count threshold",
- colexec.DefaultVectorizeRowCountThreshold,
- func(v int64) error {
- if v < 0 {
- return pgerror.Newf(pgcode.InvalidParameterValue,
- "cannot set sql.defaults.vectorize_row_count_threshold to a negative value: %d", v)
- }
- return nil
- },
-)
-
 // DistSQLClusterExecMode controls the cluster default for when DistSQL is used.
 var DistSQLClusterExecMode = settings.RegisterEnumSetting(
  "sql.defaults.distsql",
@@ -2248,10 +2231,6 @@ func (m *sessionDataMutator) SetVectorize(val sessiondatapb.VectorizeExecMode) {
  m.data.VectorizeMode = val
 }
 
-func (m *sessionDataMutator) SetVectorizeRowCountThreshold(val uint64) {
- m.data.VectorizeRowCountThreshold = val
-}
-
 func (m *sessionDataMutator) SetTestingVectorizeInjectPanics(val bool) {
  m.data.TestingVectorizeInjectPanics = val
 }

pkg/sql/explain_plan.go

@@ -85,12 +85,9 @@ func (e *explainPlanNode) startExec(params runParams) error {
  flowCtx := newFlowCtxForExplainPurposes(planCtx, params.p, &distSQLPlanner.rpcCtx.ClusterID)
 
  ctxSessionData := flowCtx.EvalCtx.SessionData
- vectorizedThresholdMet := physicalPlan.MaxEstimatedRowCount >= ctxSessionData.VectorizeRowCountThreshold
  var willVectorize bool
  if ctxSessionData.VectorizeMode == sessiondatapb.VectorizeOff {
  willVectorize = false
- } else if !vectorizedThresholdMet && ctxSessionData.VectorizeMode == sessiondatapb.VectorizeOn {
- willVectorize = false
  } else {
  willVectorize = true
  for _, flow := range flows {

pkg/sql/flowinfra/flow_test.go

@@ -35,12 +35,8 @@ func BenchmarkFlowSetup(b *testing.B) {
  defer logScope.Close(b)
  ctx := context.Background()
 
- st := cluster.MakeTestingClusterSettings()
- // Set the threshold to 0 so that we can control which engine is used for
- // the query execution via the vectorize mode.
- sql.VectorizeRowCountThresholdClusterValue.Override(&st.SV, 0 /* v */)
  s, conn, _ := serverutils.StartServer(b, base.TestServerArgs{
- Settings: st,
+ Settings: cluster.MakeTestingClusterSettings(),
  })
  defer s.Stopper().Stop(ctx)
 

pkg/sql/logictest/logic.go

@@ -1520,14 +1520,6 @@ func (t *logicTest) newCluster(serverArgs TestServerArgs) {
  }
  }
 
- // Always override the vectorize row count threshold. This runs all supported
- // queries (relative to the mode) through the vectorized execution engine.
- if _, err := conn.Exec(
- "SET CLUSTER SETTING sql.defaults.vectorize_row_count_threshold = 0",
- ); err != nil {
- t.Fatal(err)
- }
-
  if cfg.overrideAutoStats != "" {
  if _, err := conn.Exec(
  "SET CLUSTER SETTING sql.stats.automatic_collection.enabled = $1::bool", cfg.overrideAutoStats,

pkg/sql/logictest/testdata/logic_test/information_schema

@@ -3668,7 +3668,6 @@ transaction_isolation serializable
 transaction_priority normal
 transaction_read_only off
 transaction_status NoTxn
-vectorize_row_count_threshold 0
 
 # information_schema can be used with the anonymous database.
 # It should show information across all databases.

pkg/sql/logictest/testdata/logic_test/pg_catalog

@@ -2158,7 +2158,6 @@ transaction_priority normal NULL
 transaction_read_only off NULL NULL NULL string
 transaction_status NoTxn NULL NULL NULL string
 vectorize on NULL NULL NULL string
-vectorize_row_count_threshold 0 NULL NULL NULL string
 
 query TTTTTTT colnames
 SELECT
@@ -2238,7 +2237,6 @@ transaction_priority normal NULL
 transaction_read_only off NULL user NULL off off
 transaction_status NoTxn NULL user NULL NoTxn NoTxn
 vectorize on NULL user NULL on on
-vectorize_row_count_threshold 0 NULL user NULL 0 0
 
 query TTTTTT colnames
 SELECT name, source, min_val, max_val, sourcefile, sourceline FROM pg_catalog.pg_settings
@@ -2316,7 +2314,6 @@ transaction_priority NULL NULL NULL
 transaction_read_only NULL NULL NULL NULL NULL
 transaction_status NULL NULL NULL NULL NULL
 vectorize NULL NULL NULL NULL NULL
-vectorize_row_count_threshold NULL NULL NULL NULL NULL
 
 # pg_catalog.pg_sequence
 

pkg/sql/logictest/testdata/logic_test/show_source

@@ -95,7 +95,6 @@ transaction_priority normal
 transaction_read_only off
 transaction_status NoTxn
 vectorize on
-vectorize_row_count_threshold 0
 
 query T colnames
 SELECT * FROM [SHOW CLUSTER SETTING sql.defaults.distsql]

pkg/sql/logictest/testdata/logic_test/system

@@ -602,7 +602,6 @@ SELECT name, value
 FROM system.settings
 WHERE name NOT IN ('version', 'sql.defaults.distsql', 'cluster.secret',
  'sql.stats.automatic_collection.enabled', 'sql.defaults.vectorize',
- 'sql.defaults.vectorize_row_count_threshold',
  'sql.defaults.experimental_distsql_planning')
 ORDER BY name
 ----