High CPU usage during music playback
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Canonical System Image |
Confirmed
|
Medium
|
Unassigned | ||
media-hub (Ubuntu) |
New
|
Undecided
|
Unassigned |
Bug Description
When playing music I can see quite high CPU usage (about 20% altogether) by media-hub-server and pulseaudio. This seems excessive and likely causes us to use quite a lot more power than we need.
The top of top looks like so:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
2773 phablet 20 0 342008 22344 15984 S 13,0 2,3 2:53.92 media-hub-serve
2548 phablet 9 -11 368208 12028 8448 S 6,8 1,2 1:32.37 pulseaudio
16126 phablet 20 0 6284 1284 768 R 1,6 0,1 0:00.28 top
2806 phablet 20 0 524540 110060 40520 S 1,3 11,2 0:51.24 unity8
4991 phablet 20 0 389448 96144 30532 S 1,3 9,8 0:30.70 qmlscene
I suspect unity8/qmlscene are rendering playback progress unnecessarily when the screen is off, but media-hub-server and pulseaudio use about 20% CPU together.
dbus-monitor shows quite high activity every second:
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Position"
method return sender=:1.51 -> dest=:1.136 reply_serial=13885
variant int64 93624866996
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Duration"
method return sender=:1.51 -> dest=:1.136 reply_serial=13886
variant int64 306988000000
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Position"
method return sender=:1.51 -> dest=:1.136 reply_serial=13887
variant int64 93638280996
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Duration"
method return sender=:1.51 -> dest=:1.136 reply_serial=13888
variant int64 306988000000
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Position"
method return sender=:1.51 -> dest=:1.136 reply_serial=13889
variant int64 93653857996
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Position"
method return sender=:1.51 -> dest=:1.136 reply_serial=13890
variant int64 93657725996
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Duration"
method return sender=:1.51 -> dest=:1.136 reply_serial=13891
variant int64 306988000000
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Position"
method return sender=:1.51 -> dest=:1.136 reply_serial=13892
variant int64 93666179996
method call sender=:1.136 -> dest=core.
string "org.mpris.
string "Duration"
method return sender=:1.51 -> dest=:1.136 reply_serial=13893
variant int64 306988000000
:1.51 is pulseaudio, :1.136 is music app.
$ system-image-cli -i
current build number: 323
device name: krillin
channel: ubuntu-
last update: 2016-05-01 13:37:17
version version: 323
version ubuntu: 20160429
version device: 20160329-a9bacdb
version custom: 20160324-
ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: media-hub 4.1.0+15.
Uname: Linux 3.4.67 armv7l
ApportVersion: 2.17.2-0ubuntu1.8
Architecture: armhf
Date: Tue May 3 11:25:19 2016
InstallationDate: Installed on 2016-04-29 (4 days ago)
InstallationMedia: Ubuntu 15.04 - armhf (20160429-020305)
SourcePackage: media-hub
UpgradeStatus: No upgrade log present (probably fresh install)
Changed in canonical-devices-system-image: | |
status: | New → Confirmed |
importance: | Undecided → Medium |
assignee: | nobody → John McAleely (john.mcaleely) |
Changed in canonical-devices-system-image: | |
assignee: | John McAleely (john.mcaleely) → nobody |
Bug #1475678 would likely reduce the qmlscene impact - as would making it use the new playlist APIs so we can remove it from lifecycle exceptions.