Re: [lc-devel] pre4

[Rodrigo S. de C. <rc...@im...>]

On Thu, May 23, 2002 at 12:56:46PM +0200, Marc-Christian Petersen wrote:
> On Thursday 23 May 2002 03:55, Patrick wrote:
>
> > I think the setup procedures have been changed.
> > Can you give me the proper way of selecting the compress cache size and how
> > to compile it?
>
> Compiling doesn't really matter. You can give the size via bootparam
> "compsize=N" or via /proc/sys/vm/comp_cache/size

That's right. Recall that "N" is the number of memory pages to be used
by compressed cache.

> I've noticed, with "Page compressing" the system gets slower, and
> stopps reacting for less than a second if you do high i/o.

Is there any specific IO bound program you run that can make this
slowdown more noticeable? I'd like to fix this behaviour.

> With Lockbreak, not part of Compressed Cache, there are still some
> stopps, but i think, Rodrigo has this stuff on his ToDo-List.

Let me get this straight. Do you still have problems when running
compressed cache with lock-break enabled? If you do, even when the
page cache support is disabled?

> But, anyway, i cannot tell you the exact size of what it should be
> to get maximum compression and also maximum speed. I've asked this
> yesterday too on this mailinglist. :) Let's wait for Rodrigo.

I'd set to something between 15% and 25% of your total memory size
since we don't have adaptivity yet.

Regards,
-- 
Rodrigo S. de Castro <rc...@im...>