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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Hangouts in ChromeOS pegs the GPU at max frequency"
href="https://bugs.freedesktop.org/show_bug.cgi?id=110750">110750</a>
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<th>Summary</th>
<td>Hangouts in ChromeOS pegs the GPU at max frequency
</td>
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<th>Product</th>
<td>DRI
</td>
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<th>Version</th>
<td>DRI git
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<th>Hardware</th>
<td>x86-64 (AMD64)
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<th>OS</th>
<td>Linux (All)
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>major
</td>
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<th>Priority</th>
<td>medium
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<th>Component</th>
<td>DRM/Intel
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<th>Assignee</th>
<td>intel-gfx-bugs@lists.freedesktop.org
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<th>Reporter</th>
<td>nathan.d.ciobanu@linux.intel.com
</td>
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<th>QA Contact</th>
<td>intel-gfx-bugs@lists.freedesktop.org
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<th>CC</th>
<td>intel-gfx-bugs@lists.freedesktop.org
</td>
</tr></table>
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<pre>Running Hangouts on ChromeOS pegs the GPU at max frequency while the camera is
enabled.
A quicker way to reproduce this issue is to access this URL in the Chrome
browser: <a href="https://appr.tc/?debug=loopback&vsc=vp8&vrc=vp8">https://appr.tc/?debug=loopback&vsc=vp8&vrc=vp8</a>
A bisect of the ChromeOS kernel releases has pointed to this patch as the point
when this issue started occurring:
"7b92c1bd0540 - drm/i915: Avoid keeping waitboost active for signaling threads"
which has been backported to chromeos-4.4 and later kernels.
It is quite evident what the patch and the subsequent work intended to do but a
user space client like Hangouts seems to increase power consumption with no
benefit from the increased performance - IIUC. The GPU utilization is between
30 to 40% while the frequency is max at 1050MHz (on my i7 KBL-Y Pixelbook).
As an experiment we capped the max GT frequency to 500MHz and saw a drop of
about 2W with no hit to performance.
Question is: how can we improve the power consumption given the above patch in
the Hangouts case?
Note;
On Ubuntu running Hangouts in the Chrome browser we see more GPU frequency
scaling but power consumption is still really high.
Since this is more of a question I haven't included logs yet but let me know if
you want to see something and I will upload.</pre>
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