100% CPU when the History or Wallpaper Selector panels are open

Bug #1494992 reported by Samuel on 2015-09-12
22
This bug affects 3 people
Affects Status Importance Assigned to Milestone
Variety
Medium
James Lu
variety (Ubuntu)
Undecided
Unassigned
Xenial
Undecided
Unassigned
Yakkety
Undecided
Unassigned
Zesty
Undecided
Unassigned
Artful
Undecided
Unassigned

Bug Description

Version:0.5.4
DE:Cinnamon 2.6.13
OS:Linux Mint 17.2

When you chnage the backgroud in the history panel or scroll in it the CPU utilisation goes up to 100% and stay there.
I need to close the panel and reopen it to restore the utilisation back to normal.
The problem seem also to be in the download history panel and the selection of background too.

----

Below is the SRU information by James Lu (https://launchpad.net/~tacocat)

[Impact]

 * The autoscroll feature in Variety's Wallpaper Selector dialog before commit https://bazaar.launchpad.net/~variety/variety/trunk/revision/592 consumes excessive amounts of CPU after leaving the autoscroll area. This affects both the "History" and "Wallpaper Selector" options found in Variety's menu.

 * Although this bug doesn't cause any serious damage, pegging a machine's CPU is quite annoying and users will notice whirring fans and reduced battery life as a result.

 * The proposed fix adds a missing line to clear the autoscroll state when leaving the wallpaper selector. This way, the code in _autoscroll_thread() (which polls for whether the mouse is over the wallpaper selector) doesn't instantly succeed and create an infinite loop.

[Test Case]

 1) Select one or more wallpaper sources so that in the Wallpaper Selector, scrolling is needed to show all items.

 2) Open the wallpaper selector, either by focusing on a wallpaper source in the preferences dialog, or by choosing the "Wallpaper Selector" option in Variety's tray menu.

 3) Move the mouse over any of the images in the wallpaper selector.

 4) Move the mouse away from the wallpaper selector. A CPU spike in Variety should appear now.
   - Note that this CPU spike is different from any initial CPU spikes when the wallpaper selector first opens, as that is due to Variety generating all the thumbnails on the spot. The CPU spike mentioned in this bug lasts as long as the wallpaper selector is open and the mouse is not over it, while the initial spikes are temporary (they always last less than 5 seconds for me)

[Regression Potential]

 * This patch affects the autoscroll portion of the wallpaper selector. Should this patch be erroneous, some symptoms could include autoscroll or the entire wallpaper selector not working entirely.

 * Syntax or variable name errors will, on the other hand, raise Python exceptions and possibly cause Variety to fail to start entirely.

[Other Info]

 * The original patch fixing this bug was included in Debian release 0.6.3-5, which has been in Debian stretch for about 2 months and artful for a similar time (I don't remember the exact date of the relevant sync). No new bugs related to this issue have been opened since in Debian and Ubuntu.

Samuel (samuel-lague) wrote :

Linux Mint 18.1 x64 Mate-Edition
Window Manager Marco

Same Problem here.
If the mouse is on the pictures, everything is fine.
If i put the mouse outside of the pictures, my CPU is on rampage and eats little children.

James Lu (tacocat) wrote :

Confirming this on Debian stretch/sid, Variety 0.6.3, and Cinnamon 3.2.7-2. This affects not only the History panel but the Wallpaper Selector as well.

Changed in variety:
status: New → Triaged
summary: - 100% CPU when changing the backgroud in the history panel
+ 100% CPU when the History or Wallpaper Selector panels are open
Changed in variety:
importance: Undecided → Medium
James Lu (tacocat) on 2017-05-05
Changed in variety:
assignee: nobody → James Lu (tacocat)
James Lu (tacocat) on 2017-05-05
Changed in variety:
status: Triaged → Fix Committed
James Lu (tacocat) on 2017-07-08
Changed in variety (Ubuntu):
status: New → Fix Released
description: updated
description: updated

yakkety is mostly EOL, so not worth the effort probably

Changed in variety (Ubuntu Xenial):
status: New → Fix Committed
Changed in variety (Ubuntu Zesty):
status: New → Fix Committed
Changed in variety (Ubuntu Yakkety):
status: New → Incomplete
Changed in variety (Ubuntu Yakkety):
status: Incomplete → Won't Fix

Hello Samuel, or anyone else affected,

Accepted variety into zesty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/variety/0.6.3-2ubuntu1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-zesty to verification-done-zesty. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-zesty. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

tags: added: verification-needed verification-needed-zesty
Brian Murray (brian-murray) wrote :

The previous SRU of variety to xenial has not been verified in 111 days. Should this new SRU be uploaded over it or does someone want to verify it now?

Changed in variety (Ubuntu Xenial):
status: Fix Committed → Incomplete

Hi,

This SRU contains all the changes from the previous one, so it should be
ok to replace the old one.

Regarding verification, is there anyone in the verification team I
should ping to get the process started?

James

On 14/07/17 02:22 AM, Brian Murray wrote:
> The previous SRU of variety to xenial has not been verified in 111 days.
> Should this new SRU be uploaded over it or does someone want to verify
> it now?
>
> ** Changed in: variety (Ubuntu Xenial)
> Status: Fix Committed => Incomplete
>
.

Hello Samuel, or anyone else affected,

Accepted variety into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/variety/0.6.0-1ubuntu2 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-xenial to verification-done-xenial. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-xenial. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

Changed in variety (Ubuntu Xenial):
status: Incomplete → Fix Committed
tags: added: verification-needed-xenial
Brian Murray (brian-murray) wrote :

It is possible for the uploader / fixer of the bug to verify that the fix works.

James Lu (tacocat) on 2017-08-22
Changed in variety:
status: Fix Committed → Fix Released
milestone: none → 0.6.5

The fix for this bug has been awaiting testing feedback in the -proposed repository for zesty for more than 90 days. Please test this fix and update the bug appropriately with the results. In the event that the fix for this bug is still not verified 15 days from now, the package will be removed from the -proposed repository.

tags: added: removal-candidate
To post a comment you must log in.
This report contains Public information  Edit
Everyone can see this information.

Duplicates of this bug

Other bug subscribers

Bug attachments