Re: [PATCH] Significant performace improvements on reiserfs systems

[Andrea Arcangeli]

On Thu, Sep 20, 2001 at 01:19:53PM -0400, Chris Mason wrote:
> 
> 
> On Thursday, September 20, 2001 07:08:25 PM +0200 Dieter Nützel
> <[e-mail]> wrote:
> 
> 
> > Please have a look at Robert Love's Linux kernel preemption patches and
> > the  conversation about my reported latency results.
> > 
> 
> Andrew Morton has patches that significantly improve the reiserfs latency,
> looks like the last one he sent me was 2.4.7-pre9.  He and I did a bunch of
> work to make sure they introduce schedules only when it was safe.
> 
> Andrew, are these still maintained or should I pull out the reiserfs bits?

May not help latency but I suspect this could help reiserfs, it should
basically be a noop for ext2.

--- 2.4.10pre12aa2/fs/buffer.c.~1~	Thu Sep 20 20:14:19 2001
+++ 2.4.10pre12aa2/fs/buffer.c	Thu Sep 20 20:45:58 2001
@@ -2506,7 +2506,7 @@
 	spin_unlock(&free_list[isize].lock);
 
 	page->buffers = bh;
-	page->flags &= ~(1 << PG_referenced);
+	page->flags |= 1 << PG_referenced;
 	lru_cache_add(page);
 	UnlockPage(page);
 	atomic_inc(&buffermem_pages);

You may want to give it a spin.

Andrea