Files
tidb/pkg/executor/aggregate/agg_hash_base_worker.go

89 lines
3.0 KiB
Go

// Copyright 2023 PingCAP, Inc.
//
// 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 aggregate
import (
"github.com/pingcap/failpoint"
"github.com/pingcap/tidb/pkg/executor/aggfuncs"
"github.com/pingcap/tidb/pkg/sessionctx"
"github.com/pingcap/tidb/pkg/sessionctx/stmtctx"
"github.com/pingcap/tidb/pkg/util/hack"
"github.com/pingcap/tidb/pkg/util/memory"
)
// baseHashAggWorker stores the common attributes of HashAggFinalWorker and HashAggPartialWorker.
// nolint:structcheck
type baseHashAggWorker struct {
ctx sessionctx.Context
finishCh <-chan struct{}
aggFuncs []aggfuncs.AggFunc
maxChunkSize int
stats *AggWorkerStat
memTracker *memory.Tracker
BInMap int // indicate there are 2^BInMap buckets in Golang Map.
}
func newBaseHashAggWorker(ctx sessionctx.Context, finishCh <-chan struct{}, aggFuncs []aggfuncs.AggFunc,
maxChunkSize int, memTrack *memory.Tracker) baseHashAggWorker {
baseWorker := baseHashAggWorker{
ctx: ctx,
finishCh: finishCh,
aggFuncs: aggFuncs,
maxChunkSize: maxChunkSize,
memTracker: memTrack,
BInMap: 0,
}
return baseWorker
}
func (w *baseHashAggWorker) getPartialResult(_ *stmtctx.StatementContext, groupKey [][]byte, mapper aggfuncs.AggPartialResultMapper) [][]aggfuncs.PartialResult {
n := len(groupKey)
partialResults := make([][]aggfuncs.PartialResult, n)
allMemDelta := int64(0)
partialResultSize := w.getPartialResultSliceLenConsiderByteAlign()
for i := 0; i < n; i++ {
var ok bool
if partialResults[i], ok = mapper[string(groupKey[i])]; ok {
continue
}
partialResults[i] = make([]aggfuncs.PartialResult, partialResultSize)
for j, af := range w.aggFuncs {
partialResult, memDelta := af.AllocPartialResult()
partialResults[i][j] = partialResult
allMemDelta += memDelta // the memory usage of PartialResult
}
allMemDelta += int64(partialResultSize * 8)
// Map will expand when count > bucketNum * loadFactor. The memory usage will double.
if len(mapper)+1 > (1<<w.BInMap)*hack.LoadFactorNum/hack.LoadFactorDen {
w.memTracker.Consume(hack.DefBucketMemoryUsageForMapStrToSlice * (1 << w.BInMap))
w.BInMap++
}
mapper[string(groupKey[i])] = partialResults[i]
allMemDelta += int64(len(groupKey[i]))
}
failpoint.Inject("ConsumeRandomPanic", nil)
w.memTracker.Consume(allMemDelta)
return partialResults
}
func (w *baseHashAggWorker) getPartialResultSliceLenConsiderByteAlign() int {
length := len(w.aggFuncs)
if length == 1 {
return 1
}
return length + length&1
}