Re: [PATCH 0/4] linux-2.6-block: deactivating pagecache forbenchmarks

From: Lee Revell
Date: Mon Dec 05 2005 - 11:24:13 EST


On Sun, 2005-12-04 at 20:13 -0600, Rob Landley wrote:
> > Add /proc/sys/vm/drop-pagecache. When written to, this will cause the
> > kernel to discard as much pagecache and reclaimable slab objects as it can.
> >
> > It won't drop dirty data, so the user should run `sync' first.
>
> This is deeply, deeply cool.
>
> > Caveats:
> >
> > a) Holds inode_lock for exorbitant amounts of time.
>
> Voluntary preemption point, maybe?

I thin it's a bad idea, that would just encourage people to use this for
anything other than debugging. If you care about latency don't discard
the page cache.

The GNOME people have been asking for this for a while, in order to
improve startup times, they would like a way to simulate a cold start
without rebooting.

Lee

-
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/