好久没写技术的内容了, 要长草了 随便写一篇今天的吧 ( 同事发现的我只是搬运工 ) 现象: 在部分跑着 mongodb 的机器上跑 puppet , 巨卡, 竟然需要跑好几十分钟, 并且 top 看起来还是 system 占用的 cpu 资源而不是 user . 解决: 因为众所周知的原因, 跑 mong
好久没写技术的内容了, 要长草了… 随便写一篇今天的吧 ( 同事发现的…我只是搬运工 )
现象: 在部分跑着 mongodb 的机器上跑 puppet , 巨卡, 竟然需要跑好几十分钟, 并且 top 看起来还是 system 占用的 cpu 资源而不是 user .
解决:
因为众所周知的原因, 跑 mongodb 时必须关闭 NUMA 来启动. 看了以下这个页面, 才发现还需要关闭?zone_reclaim_mode. 因为此值默认总是关闭的, 所以一直没有为意.
http://docs.mongodb.org/manual/administration/production-notes/#production-numa
因为某些原因, 我们上周开启了 /proc/sys/vm/zone_reclaim_mode, 导致的问题.
http://www.kernel.org/doc/Documentation/sysctl/vm.txt , 已经提醒过大家, 最好关闭了.
http://www.poempelfox.de/blog/2010/03/, 解释最全了.?阐述了多种症状, 我们都命中了…例如一个普通的系统调用需时甚长.
唉, 关闭了?zone_reclaim_mode 就好了.
原文地址:puppet 在 mongodb 的机器上卡死, 感谢原作者分享。

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