Re: Ability to limit or disable page caching?

["Kevin Burton" <burton@tailrank.com>]

> One of the problems is that the process pages (anonymous memory) and
> page cache pages live on the same LRU, so the kernel cannot always
> easily find the page cache pages when it is trying to evict something.

Ah... that makes sense.

> Once that is fixed, and replacement is biased towards evicting page
> cache pages, the system may do the right thing by itself.

Yeah.  That seems like it...

> I have no such tunable in my code (yet), because I would like the
> kernel to do the right thing automatically.  I will post a 2.6.25 based
> kernel RPM for Fedora 9 soon with the split LRU patch series applied.

With the same patch you linked to above?  No new code..

We're on Debian so I need to dive in and see how easy it would be for
us to compile our own kernel.

I've done it in the past but I've avoided running anything non-stock
for about 2 years now...

We're on 2.6.24 though but that's not a big issue.

> If you feel like testing/breaking it, I would be interested to see if
> it does indeed do the right thing for your workload or if it needs more
> tuning.

Well we'd be deploying it in product :).. what's the ETA into making
it into the official kernel?

Kevin


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