github.com/kafkaliu/etcd@v0.1.2-0.20131007164923-44c16dd30d69/snapshot.go (about) 1 /* 2 Copyright 2013 CoreOS Inc. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 */ 16 17 package main 18 19 import ( 20 "time" 21 ) 22 23 // basic conf. 24 // TODO: find a good policy to do snapshot 25 type snapshotConf struct { 26 // Etcd will check if snapshot is need every checkingInterval 27 checkingInterval time.Duration 28 // The number of writes when the last snapshot happened 29 lastWrites uint64 30 // If the incremental number of writes since the last snapshot 31 // exceeds the write Threshold, etcd will do a snapshot 32 writesThr uint64 33 } 34 35 var snapConf *snapshotConf 36 37 func newSnapshotConf() *snapshotConf { 38 // check snapshot every 3 seconds and the threshold is 20K 39 return &snapshotConf{time.Second * 3, etcdStore.TotalWrites(), 20 * 1000} 40 } 41 42 func monitorSnapshot() { 43 for { 44 time.Sleep(snapConf.checkingInterval) 45 currentWrites := etcdStore.TotalWrites() - snapConf.lastWrites 46 47 if currentWrites > snapConf.writesThr { 48 r.TakeSnapshot() 49 snapConf.lastWrites = etcdStore.TotalWrites() 50 } 51 } 52 }