From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] cache lines, and 60000 cycles of doom
Date: Fri, 20 Jun 2014 07:45:30 -0400 [thread overview]
Message-ID: <4a81bb5db0670710c6126ad8f7f22d4b@brasstown.quanstro.net> (raw)
In-Reply-To: <20140620050945.6C4E7B827@mail.bitblocks.com>
> > the astounding thing is that t1-t0 is often ~ 60,000 cycles.
> > it only hits a small fraction of the time, and the average is
> > much lower. but that just blows the mind. 60000 cycles!
> >
> > (other versions with sched were much worse.)
> >
> > as far as i can tell, there are no funny bits in the scheduler that
> > can cause this, and no wierd scheduling is going on.
> >
> > i'm baffled.
>
> Could there've been a context switch?
the file server does not have context switches.
- erik
prev parent reply other threads:[~2014-06-20 11:45 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-19 16:01 erik quanstrom
2014-06-20 5:03 ` Devon H. O'Dell
2014-06-20 11:50 ` erik quanstrom
2014-06-20 12:47 ` Devon H. O'Dell
2014-06-20 13:07 ` erik quanstrom
2014-06-20 5:09 ` Bakul Shah
2014-06-20 11:45 ` erik quanstrom [this message]
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