github.com/whtcorpsinc/milevadb-prod@v0.0.0-20211104133533-f57f4be3b597/soliton/systimemon/systime_mon.go (about)

     1  // Copyright 2020 WHTCORPS INC, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package systimemon
    15  
    16  import (
    17  	"time"
    18  
    19  	"github.com/whtcorpsinc/milevadb/soliton/logutil"
    20  	"go.uber.org/zap"
    21  )
    22  
    23  // StartMonitor calls systimeErrHandler if system time jump backward.
    24  func StartMonitor(now func() time.Time, systimeErrHandler func(), successCallback func()) {
    25  	logutil.BgLogger().Info("start system time monitor")
    26  	tick := time.NewTicker(100 * time.Millisecond)
    27  	defer tick.Stop()
    28  	tickCount := 0
    29  	for {
    30  		last := now().UnixNano()
    31  		<-tick.C
    32  		if now().UnixNano() < last {
    33  			logutil.BgLogger().Error("system time jump backward", zap.Int64("last", last))
    34  			systimeErrHandler()
    35  		}
    36  		// call sucessCallback per second.
    37  		tickCount++
    38  		if tickCount >= 10 {
    39  			tickCount = 0
    40  			successCallback()
    41  		}
    42  	}
    43  }