Re: [patch/rft] jbd2: tag journal writes as metadata I/O

[Jeff Moyer <jmoyer@redhat.com>]

tytso@mit.edu writes:

> On Mon, Apr 05, 2010 at 02:36:07PM -0400, Jeff Moyer wrote:
>> >
>> > What benchmark were you using to test small file writes?  This looks
>> > good to me as well, but we might want to do some extra benchmarking
>> > just to be sure we're not accidentally introducing a performance
>> > regression.
>> 
>> iozone showed regressions for write and re-write in runs that include
>> fsync timings for small files (<8MB).  Here's the command line used for
>> testing:
>> 
>> iozone -az -n 4k -g 2048m -y 1k -q 1m -e
>
> iozone is showing performance regressions or performance improvements?
> I thought the point of this patch was to improve iozone benchmarks?

Sorry, Ted, what I meant to say was that iozone showed differences
between deadline and cfq, where cfq's performance was much worse than
deadline's.

Thanks!
Jeff