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https://issues.apache.org/jira/browse/IMPALA-7252?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Todd Lipcon reassigned IMPALA-7252:
-----------------------------------

    Assignee: Tianyi Wang  (was: Todd Lipcon)

I think [~tianyiwang] was actually working on this, reassigning to him.

> Backport rate limiting of fadvise calls into toolchain glog
> -----------------------------------------------------------
>
>                 Key: IMPALA-7252
>                 URL: https://issues.apache.org/jira/browse/IMPALA-7252
>             Project: IMPALA
>          Issue Type: Improvement
>          Components: Backend
>    Affects Versions: Impala 3.0
>            Reporter: Todd Lipcon
>            Assignee: Tianyi Wang
>            Priority: Major
>
> Currently, glog's default behavior is to call fadvise(FADV_DONTNEED) on the 
> log file after each entry that is written. In many versions of the Linux 
> kernel, each invocation of this call causes work to be scheduled on all other 
> CPUs, causing up to one context switch per CPU for every log line. We saw 
> this cause an extremely long GC pause in the catalogd in the case where the 
> native side of the catalog was logging a lot of messages about publishing 
> metadata updates at the same time that the Java side was running a GC. The GC 
> spent almost all of its time in the kernel due to the high context switch 
> rate causing a lot of TLB clears and misses, and instead of pausing the JVM 
> for a couple of seconds took several minutes.
> This was identified and fixed upstream in glog here: 
> https://github.com/google/glog/commit/dacd29679633c9b845708e7015bd2c79367a6ea2
> We should backport this fix into the version in the toolchain.



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