Files
tidb/pkg/executor/join/hash_join_spill.go
2024-10-22 03:27:44 +00:00

90 lines
2.6 KiB
Go

// Copyright 2024 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 join
import (
"github.com/pingcap/tidb/pkg/util/memory"
)
// This variable should be const, but we need to modify it for test
var spillChunkSize = 1024
const spillInfo = "memory exceeds quota, spill to disk now."
const (
notSpilled = iota
needSpill
inSpilling
)
type hashJoinSpillAction struct {
memory.BaseOOMAction
spillHelper *hashJoinSpillHelper
}
func newHashJoinSpillAction(spillHelper *hashJoinSpillHelper) *hashJoinSpillAction {
return &hashJoinSpillAction{
spillHelper: spillHelper,
}
}
// GetPriority get the priority of the Action.
func (*hashJoinSpillAction) GetPriority() int64 {
return memory.DefSpillPriority
}
func (h *hashJoinSpillAction) Action(t *memory.Tracker) {
if h.actionImpl(t) {
return
}
if t.CheckExceed() && (!hasEnoughDataToSpill(h.spillHelper.hashJoinExec.memTracker, t) || !h.spillHelper.canSpill()) {
h.triggerFallBackAction(t)
}
}
func (h *hashJoinSpillAction) triggerFallBackAction(t *memory.Tracker) {
if fallback := h.GetFallback(); fallback != nil {
fallback.Action(t)
}
}
// Return true if it successfully sets spill flag
func (h *hashJoinSpillAction) actionImpl(t *memory.Tracker) bool {
h.spillHelper.cond.L.Lock()
defer h.spillHelper.cond.L.Unlock()
for h.spillHelper.isInSpillingNoLock() {
h.spillHelper.cond.Wait()
}
if t.CheckExceed() && h.spillHelper.isNotSpilledNoLock() && hasEnoughDataToSpill(h.spillHelper.hashJoinExec.memTracker, t) && h.spillHelper.canSpill() {
h.spillHelper.setNeedSpillNoLock()
// Because all executors could keep running before spill flag is set to `inSpilling`, memory
// consumption will be modified before we print the spill log. It's necessary to record the
// memory consumption when spill is triggered.
h.spillHelper.bytesConsumed.Store(t.BytesConsumed())
h.spillHelper.bytesLimit.Store(t.GetBytesLimit())
return true
}
return false
}
func hasEnoughDataToSpill(hashJoinTracker *memory.Tracker, passedInTracker *memory.Tracker) bool {
return hashJoinTracker.BytesConsumed() >= passedInTracker.GetBytesLimit()/20
}