From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Date: Thu, 12 Jan 2006 19:58:28 +0000 Subject: Re: SDP perf drop with 2.6.15 Message-Id: <20060112195828.GD9256@mellanox.co.il> List-Id: References: <20060112195004.GK3106@esmail.cup.hp.com> In-Reply-To: <20060112195004.GK3106@esmail.cup.hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Quoting r. Grant Grundler : > Subject: Re: SDP perf drop with 2.6.15 > > On Thu, Jan 12, 2006 at 09:18:03AM +0200, Michael S. Tsirkin wrote: > > > Makes me think it's a change in the interrupt code path. > > > Any clues on where I might start with this? > > > > oprofile should show where we are spending the time. > > Executive summary: > Silly me. interrupt bindings changed and I didn't check after rolling > to 2.6.15 (from 2.6.14). That explains the increase cpu utilization > with lower performance. > Getting similar performance with -T 0,0 (2.6.15) vs -T 1,1 (2.6.14). > OK, so we are left with the ref count now. I'm seeing this myself sometimes, I have some other stuff to attend to next week, and then I plan to look into this. -- MST