Re: huge tlb support

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.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company