| // Copyright 2016 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 ( |
| "sync" |
| "time" |
| |
| pb "github.com/coreos/etcd/etcdserver/etcdserverpb" |
| "github.com/coreos/etcd/mvcc" |
| "github.com/coreos/pkg/capnslog" |
| "github.com/jonboulle/clockwork" |
| "golang.org/x/net/context" |
| ) |
| |
| var ( |
| plog = capnslog.NewPackageLogger("github.com/coreos/etcd", "compactor") |
| ) |
| |
| const ( |
| checkCompactionInterval = 5 * time.Minute |
| executeCompactionInterval = time.Hour |
| ) |
| |
| type Compactable interface { |
| Compact(ctx context.Context, r *pb.CompactionRequest) (*pb.CompactionResponse, error) |
| } |
| |
| type RevGetter interface { |
| Rev() int64 |
| } |
| |
| // Periodic compacts the log by purging revisions older than |
| // the configured retention time. Compaction happens hourly. |
| type Periodic struct { |
| clock clockwork.Clock |
| periodInHour int |
| |
| rg RevGetter |
| c Compactable |
| |
| revs []int64 |
| ctx context.Context |
| cancel context.CancelFunc |
| |
| mu sync.Mutex |
| paused bool |
| } |
| |
| func NewPeriodic(h int, rg RevGetter, c Compactable) *Periodic { |
| return &Periodic{ |
| clock: clockwork.NewRealClock(), |
| periodInHour: h, |
| rg: rg, |
| c: c, |
| } |
| } |
| |
| func (t *Periodic) Run() { |
| t.ctx, t.cancel = context.WithCancel(context.Background()) |
| t.revs = make([]int64, 0) |
| clock := t.clock |
| |
| go func() { |
| last := clock.Now() |
| for { |
| t.revs = append(t.revs, t.rg.Rev()) |
| select { |
| case <-t.ctx.Done(): |
| return |
| case <-clock.After(checkCompactionInterval): |
| t.mu.Lock() |
| p := t.paused |
| t.mu.Unlock() |
| if p { |
| continue |
| } |
| } |
| |
| if clock.Now().Sub(last) < executeCompactionInterval { |
| continue |
| } |
| |
| rev, remaining := t.getRev(t.periodInHour) |
| if rev < 0 { |
| continue |
| } |
| |
| plog.Noticef("Starting auto-compaction at revision %d", rev) |
| _, err := t.c.Compact(t.ctx, &pb.CompactionRequest{Revision: rev}) |
| if err == nil || err == mvcc.ErrCompacted { |
| t.revs = remaining |
| last = clock.Now() |
| plog.Noticef("Finished auto-compaction at revision %d", rev) |
| } else { |
| plog.Noticef("Failed auto-compaction at revision %d (%v)", err, rev) |
| plog.Noticef("Retry after %v", checkCompactionInterval) |
| } |
| } |
| }() |
| } |
| |
| func (t *Periodic) Stop() { |
| t.cancel() |
| } |
| |
| func (t *Periodic) Pause() { |
| t.mu.Lock() |
| defer t.mu.Unlock() |
| t.paused = true |
| } |
| |
| func (t *Periodic) Resume() { |
| t.mu.Lock() |
| defer t.mu.Unlock() |
| t.paused = false |
| } |
| |
| func (t *Periodic) getRev(h int) (int64, []int64) { |
| i := len(t.revs) - int(time.Duration(h)*time.Hour/checkCompactionInterval) |
| if i < 0 { |
| return -1, t.revs |
| } |
| return t.revs[i], t.revs[i+1:] |
| } |