prometheus/tsdb/ooo_isolation.go

80 lines
1.9 KiB
Go

// Copyright 2023 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
import (
"container/list"
"sync"
"github.com/prometheus/prometheus/tsdb/chunks"
)
type oooIsolation struct {
mtx sync.RWMutex
openReads *list.List
}
type oooIsolationState struct {
i *oooIsolation
e *list.Element
minRef chunks.ChunkDiskMapperRef
}
func newOOOIsolation() *oooIsolation {
return &oooIsolation{
openReads: list.New(),
}
}
// HasOpenReadsAtOrBefore returns true if this oooIsolation is aware of any reads that use
// chunks with reference at or before ref.
func (i *oooIsolation) HasOpenReadsAtOrBefore(ref chunks.ChunkDiskMapperRef) bool {
i.mtx.RLock()
defer i.mtx.RUnlock()
for e := i.openReads.Front(); e != nil; e = e.Next() {
s := e.Value.(*oooIsolationState)
if ref.GreaterThan(s.minRef) {
return true
}
}
return false
}
// TrackReadAfter records a read that uses chunks with reference after minRef.
//
// The caller must ensure that the returned oooIsolationState is eventually closed when
// the read is complete.
func (i *oooIsolation) TrackReadAfter(minRef chunks.ChunkDiskMapperRef) *oooIsolationState {
s := &oooIsolationState{
i: i,
minRef: minRef,
}
i.mtx.Lock()
s.e = i.openReads.PushBack(s)
i.mtx.Unlock()
return s
}
func (s oooIsolationState) Close() {
s.i.mtx.Lock()
s.i.openReads.Remove(s.e)
s.i.mtx.Unlock()
}