blob: 927e41c97fafb10f47f19599242fc1344ed420f6 [file] [log] [blame]
// Copyright 2017 The etcd 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 compactor
import (
"context"
"sync"
"time"
pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
"github.com/coreos/etcd/mvcc"
"github.com/jonboulle/clockwork"
)
// Revision compacts the log by purging revisions older than
// the configured reivison number. Compaction happens every 5 minutes.
type Revision struct {
clock clockwork.Clock
retention int64
rg RevGetter
c Compactable
ctx context.Context
cancel context.CancelFunc
mu sync.Mutex
paused bool
}
// NewRevision creates a new instance of Revisonal compactor that purges
// the log older than retention revisions from the current revision.
func NewRevision(retention int64, rg RevGetter, c Compactable) *Revision {
return newRevision(clockwork.NewRealClock(), retention, rg, c)
}
func newRevision(clock clockwork.Clock, retention int64, rg RevGetter, c Compactable) *Revision {
t := &Revision{
clock: clock,
retention: retention,
rg: rg,
c: c,
}
t.ctx, t.cancel = context.WithCancel(context.Background())
return t
}
const revInterval = 5 * time.Minute
// Run runs revision-based compactor.
func (t *Revision) Run() {
prev := int64(0)
go func() {
for {
select {
case <-t.ctx.Done():
return
case <-t.clock.After(revInterval):
t.mu.Lock()
p := t.paused
t.mu.Unlock()
if p {
continue
}
}
rev := t.rg.Rev() - t.retention
if rev <= 0 || rev == prev {
continue
}
plog.Noticef("Starting auto-compaction at revision %d (retention: %d revisions)", rev, t.retention)
_, err := t.c.Compact(t.ctx, &pb.CompactionRequest{Revision: rev})
if err == nil || err == mvcc.ErrCompacted {
prev = rev
plog.Noticef("Finished auto-compaction at revision %d", rev)
} else {
plog.Noticef("Failed auto-compaction at revision %d (%v)", rev, err)
plog.Noticef("Retry after %v", revInterval)
}
}
}()
}
// Stop stops revision-based compactor.
func (t *Revision) Stop() {
t.cancel()
}
// Pause pauses revision-based compactor.
func (t *Revision) Pause() {
t.mu.Lock()
defer t.mu.Unlock()
t.paused = true
}
// Resume resumes revision-based compactor.
func (t *Revision) Resume() {
t.mu.Lock()
defer t.mu.Unlock()
t.paused = false
}