Re: [REGRESSION] 2.6.19/2.6.20-rc3 buffered write slowdown

Christoph Lameter
2007-01-12T03:04:50Z

On Fri, 12 Jan 2007, Nick Piggin wrote:

> Ah yes... Can't you force it on if you have a NUMA complied kernel?

But it wont do anything since it only comes into action if you have an off
node allocation. If you run a NUMA kernel on an SMP system then you only
have one node. There is no way that an off node allocation can occur.

> > zone reclaim was already in 2.6.16.
>
> Well it was a long shot, but that is something that has had a few
> changes recently and is something that could interact badly with
> the global pdflush.

zone reclaim is not touching dirty pages in its default configuration. It
would only remove up clean pagecache pages.