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Re: OT (slightly) swap limits



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On 04/26/08 18:13, Bob Proulx wrote:
[snip]
> 
> I learned about this because I didn't know it when I set up a computer
> server pool to be used for some large memory consuming simulations.
> They all had 16G of RAM with 64-bit process space.  I knew that if
> they started swapping that they would run to slowly for us and the
> plan was to avoid swapping.  If they don't swap they don't need swap
> space and so I didn't configure any on them.  I came from a Unix
> background and didn't expect this different behavior when running on
> Linux.  We started to see processes randomly stop running.  Nothing
> was ever logged from the log files for those processes.  Large memory
> applications never recorded being out of memory.  They just stopped
> running.  A number of folks started cursing Linux for being unreliable
> and at that moment for us it was very unreliable!  It was from that
> experience I learned about the Linux memory overcommit and oom killer
> behavior.  And with that knowledge I knew that I needed to rebuild the
> computer server pool with overcommit off and enough VM.
> 
[snip]

This was a very interesting post.  Just now I modified sysconf and
boosted swap up to 2x RAM.

- --
Ron Johnson, Jr.
Jefferson LA  USA

We want... a Shrubbery!!
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