Re: huge tlb support

On Tuesday, August 21, 2012 05:30:28 PM Robert Haas wrote:
> On Thu, Aug 16, 2012 at 10:53 PM, David Gould <daveg@sonic.net> wrote:
> > A warning, on RHEL 6.1 (2.6.32-131.4.1.el6.x86_64 #1 SMP) we have had
> > horrible problems caused by transparent_hugepages running postgres on
> > largish systems (128GB to 512GB memory, 32 cores). The system sometimes
> > goes 99% system time and is very slow and unresponsive to the point of
> > not successfully completing new tcp connections. Turning off
> > transparent_hugepages fixes it.
> 
> Yikes!  Any idea WHY that happens?
> 
> I'm inclined to think this torpedos any idea we might have of enabling
> hugepages automatically whenever possible.  I think we should just add
> a GUC for this and call it good.  If the state of the world improves
> sufficiently in the future, we can adjust, but I think for right now
> we should just do this in the simplest way possible and move on.
He is talking about transparent hugepages not hugepages afaics.

Andres
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