From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Subject: Re: [PATCH] drm/i915: Aggressively downclock Baytrail Date: Thu, 3 Jul 2014 08:49:22 -0700 Message-ID: <20140703084922.55e74539@jbarnes-desktop> References: <1404397766-24449-1-git-send-email-chris@chris-wilson.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pd0-f171.google.com (mail-pd0-f171.google.com [209.85.192.171]) by gabe.freedesktop.org (Postfix) with ESMTP id 554856E1CB for ; Thu, 3 Jul 2014 08:48:37 -0700 (PDT) Received: by mail-pd0-f171.google.com with SMTP id fp1so415181pdb.30 for ; Thu, 03 Jul 2014 08:48:37 -0700 (PDT) In-Reply-To: <1404397766-24449-1-git-send-email-chris@chris-wilson.co.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Chris Wilson Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Thu, 3 Jul 2014 15:29:26 +0100 Chris Wilson wrote: > Baytrail uses the RPS wait-boosting mechanism of Sandybridge+ but also has > a very lax downclocking strategy (upclock if more than 90% busy over 76ms, > downclock if less than 70% busy over 450ms). This causes Baytrail to use > maximum clocks, and for them to stay high, when doing simple tasks such as > scrolling through webpages. However, we can take a leaf out of the same > wait-boost mechansim and apply the aggressive downclocking strategy from > Sandybridge+ as well. > > Signed-off-by: Chris Wilson > --- We really need a thorough test suite to cover stuff like this, mapping frequency, power, and total energy over a big set of workloads to make sure we're not adding big regressions. I know you have the cairo traces, but did you also try this with a GL benchmark suite? I'm like the change (well you did mix in a cleanup to set_rps_thresholds), I just want us to get better at collecting numbers for this stuff... -- Jesse Barnes, Intel Open Source Technology Center