strange performance differences of 1.2.2 vs 1.2.5
brian at tangent.org
Mon Jun 2 01:31:55 UTC 2008
BTW back when we were looking at this change this was the blog post I
While I suspect that the gettimeofday() is an issue for FreeBSD if its
call is that much slower then Linux, I am having some doubts about
this being the reason behind the issue at hand. Still, every little
thing can help.
On Jun 2, 2008, at 8:30 AM, Sean Chittenden wrote:
>> That's a good guess (Brian? You know about that?:) ... but a bit
>> That gettimeofday(2) call that was changed is only made once per
>> asyncronously. In order to have such a large performance impact
>> we'd be
>> looking at some more broad changes.
> Hrm.... yeah, it's wrapped in an evtimer_set(3) call. Wait...
> libevent(3's gettime() static function will use gettimeofday(2) if
> either HAVE_CLOCK_GETTIME and CLOCK_MONOTONIC aren't defined and
> use_monotonic is false. Chris, I haven't profiled anything but it
> may be worth looking into upgrading libevent(3) since it seems as
> though the gettimeofday(2)/gettime() foo was still being toyed with
> around the timeframe of libevent 1.3. YMMV as this was only a
> passing glance at the problem w/ the details provided. :~)
> gprof(1) memcached(8) if you want more specific guidance as to what
> it could be. -sc
> Sean Chittenden
> sean at chittenden.org
Brian "Krow" Aker, brian at tangent.org
http://krow.net/ <-- Me
http://tangent.org/ <-- Software
You can't grep a dead tree.
More information about the memcached