Re: Out of memory on SELECT in 8.3.5

* Matt Magoffin (postgresql(dot)org(at)msqr(dot)us) wrote:
> Yes... and indeed changing vm.overcommit_ratio to 80 does allow that
> previously-failing query to execute successfully. Do you think this is
> also what caused the out-of-memory error we saw today just when a
> transaction was initiated?

Almost certainly.. You were running close to the edge *system-wide* on
memory allocations based on your meminfo results. You'll want to keep
an eye on the limit vs. the committed amount going forward so as to
avoid this happening in the future. It's just about the same as
watching how you're doing on overall memory usage in the box or on swap
usage. Set up some nagios monitoring, and alarm once
Committed_As/CommitLimit goes over 90%.

Thanks,

Stephen