Re: [RFC] changes to buffer.c (was Test12 ll_rw_block error)

Chris Mason
2000-12-29T16:34:25Z

On Thursday, December 28, 2000 11:29:01 AM -0800 Linus Torvalds
<torvalds@transmeta.com> wrote:
[ skipping io on the first walk in page_launder ]
>
> There are some arguments for starting the writeout early, but there are
> tons of arguments against it too (the main one being "avoid doing IO if
> you can do so"), so your patch is probably fine. In the end, the
> performance characteristics are what matters. Does the patch make for
> smoother behaviour and better performance?

My dbench speeds have always varied from run to run, but the average speed
went up about 9% with the anon space mapping patch and the page_launder
change. I could not find much difference in a pure test13-pre4, probably
because dbench doesn't generate much swap on my machine. I'll do more
tests when I get back on Monday night.

Daniel, sounds like dbench varies less on your machine, what did the patch
do for you?

BTW, the last anon space mapping patch I sent also works on test13-pre5.
The block_truncate_page fix does help my patch, since I have bdflush
locking pages ( thanks Marcelo )

-chris