terraform/vendor/github.com/cihub/seelog/behavior_adaptivelogger.go

130 lines
4.3 KiB
Go

// Copyright (c) 2012 - Cloud Instruments Co., Ltd.
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
package seelog
import (
"errors"
"fmt"
"math"
"time"
)
var (
adaptiveLoggerMaxInterval = time.Minute
adaptiveLoggerMaxCriticalMsgCount = uint32(1000)
)
// asyncAdaptiveLogger represents asynchronous adaptive logger which acts like
// an async timer logger, but its interval depends on the current message count
// in the queue.
//
// Interval = I, minInterval = m, maxInterval = M, criticalMsgCount = C, msgCount = c:
// I = m + (C - Min(c, C)) / C * (M - m)
type asyncAdaptiveLogger struct {
asyncLogger
minInterval time.Duration
criticalMsgCount uint32
maxInterval time.Duration
}
// NewAsyncLoopLogger creates a new asynchronous adaptive logger
func NewAsyncAdaptiveLogger(
config *logConfig,
minInterval time.Duration,
maxInterval time.Duration,
criticalMsgCount uint32) (*asyncAdaptiveLogger, error) {
if minInterval <= 0 {
return nil, errors.New("async adaptive logger min interval should be > 0")
}
if maxInterval > adaptiveLoggerMaxInterval {
return nil, fmt.Errorf("async adaptive logger max interval should be <= %s",
adaptiveLoggerMaxInterval)
}
if criticalMsgCount <= 0 {
return nil, errors.New("async adaptive logger critical msg count should be > 0")
}
if criticalMsgCount > adaptiveLoggerMaxCriticalMsgCount {
return nil, fmt.Errorf("async adaptive logger critical msg count should be <= %s",
adaptiveLoggerMaxInterval)
}
asnAdaptiveLogger := new(asyncAdaptiveLogger)
asnAdaptiveLogger.asyncLogger = *newAsyncLogger(config)
asnAdaptiveLogger.minInterval = minInterval
asnAdaptiveLogger.maxInterval = maxInterval
asnAdaptiveLogger.criticalMsgCount = criticalMsgCount
go asnAdaptiveLogger.processQueue()
return asnAdaptiveLogger, nil
}
func (asnAdaptiveLogger *asyncAdaptiveLogger) processItem() (closed bool, itemCount int) {
asnAdaptiveLogger.queueHasElements.L.Lock()
defer asnAdaptiveLogger.queueHasElements.L.Unlock()
for asnAdaptiveLogger.msgQueue.Len() == 0 && !asnAdaptiveLogger.Closed() {
asnAdaptiveLogger.queueHasElements.Wait()
}
if asnAdaptiveLogger.Closed() {
return true, asnAdaptiveLogger.msgQueue.Len()
}
asnAdaptiveLogger.processQueueElement()
return false, asnAdaptiveLogger.msgQueue.Len() - 1
}
// I = m + (C - Min(c, C)) / C * (M - m) =>
// I = m + cDiff * mDiff,
// cDiff = (C - Min(c, C)) / C)
// mDiff = (M - m)
func (asnAdaptiveLogger *asyncAdaptiveLogger) calcAdaptiveInterval(msgCount int) time.Duration {
critCountF := float64(asnAdaptiveLogger.criticalMsgCount)
cDiff := (critCountF - math.Min(float64(msgCount), critCountF)) / critCountF
mDiff := float64(asnAdaptiveLogger.maxInterval - asnAdaptiveLogger.minInterval)
return asnAdaptiveLogger.minInterval + time.Duration(cDiff*mDiff)
}
func (asnAdaptiveLogger *asyncAdaptiveLogger) processQueue() {
for !asnAdaptiveLogger.Closed() {
closed, itemCount := asnAdaptiveLogger.processItem()
if closed {
break
}
interval := asnAdaptiveLogger.calcAdaptiveInterval(itemCount)
<-time.After(interval)
}
}