Re: [PATCH v3 0/5] Rework mtime and ctime updates on mmaped writes

[Jan Kara <jack@xxxxxxx>]

On Thu 22-08-13 17:03:16, Andy Lutomirski wrote:
> Writes via mmap currently update mtime and ctime in ->page_mkwrite.
> This hurts both throughput and latency.  In workloads that dirty a
> large number of mmapped pages, ->page_mkwrite can be hot and
> file_update_time is slow and scales poorly.  Updating timestamps can
> also sleep, which hurts latency for real-time workloads.
  It would help to make your case if you posted the latency comparison
before & after the patchset in this introductory email. We can then see
how significant is the reduction of latency...

                                                                Honza
-- 
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR