Re: [RFC] Limit the size of the pagecache

From: Erik Andersen
Date: Wed Jan 24 2007 - 15:14:53 EST


On Wed Jan 24, 2007 at 06:58:42AM -0800, Christoph Lameter wrote:
> On Wed, 24 Jan 2007, Nick Piggin wrote:
>
> > I can't argue that a smaller pagecache will be subject to a
> > higher turnaround given the same workload, but I don't know why
> > that would be a good thing.
>
> Neither do I. Wonder why we need this but I keep getting
> these requests. Could we either find a reason for limiting the pagecache
> or get this out of our system for good?

I think this paints with too broad a brushstroke...

Simply limiting the page cache with no regard to the potential
for particular content to be later reused seems a rather
pointless exercise which is guaranteed to diminish system
performance.

It would be far more useful if an application could hint to the
pagecache as to which files are and which files as not worth
caching, especially when the application knows a priori that data
from a particular file will or will not ever be reused.

-Erik

--
Erik B. Andersen http://codepoet-consulting.com/
--This message was written using 73% post-consumer electrons--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/