[20130919]出现有持续性的Lazy Write-Mysql Tutorial-php.cn

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[20130919]出现有持续性的Lazy Write

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Jun 07, 2016 pm 05:39 PM

lazywrite

公告 [20130919]出现有持续性的Lazy Write 表现：收到性能告警，LazyWrite严重超标，一般在100以上，正常情况下，LazyWrite为0，但是奇怪的是，当时的Free pages =312190左右，相当于2G空闲空间。OS的可用内存在1G左右，从ring_buffers也没有看到外部内存压

公告

[20130919]出现有持续性的Lazy Write

表现：收到性能告警，，LazyWrite严重超标，一般在100以上，正常情况下，LazyWrite为0，但是奇怪的是，当时的Free pages =312190左右，相当于2G空闲空间。OS的可用内存在1G左右，从ring_buffers也没有看到外部内存压力，下班之后发现，tempdb开辟了一些空间。

原因：出现这个问题的原因，根据每5分钟抓取一次性能值看出，是在一个批量处理数据之后出现的。数据大概120W左右，大概的空间367MB。请教了一个资深DBA，他大概的意思是，大批量数据操作，导致数据页被逐出，现在有需要读取数据页，重新读入，发生LazyWrite。但是有一个地方解释不通的就是有大量的free pages 为什么还会Lazy Write，是否有之后的tempdb开辟了空间有关。是否和tempdb 有关目前还不知。

解决方法：经过一段时间的Lazy Write，自然便的正常

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