Bug 138175

Summary: Writer maxes out CPU core when table has dotted/dashed borders
Product: LibreOffice Reporter: Peter Ryan <peterx14>
Component: WriterAssignee: Not Assigned <libreoffice-bugs>
Status: RESOLVED WORKSFORME    
Severity: normal CC: dgp-mail
Priority: medium    
Version: 6.4.6.2 release   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
Whiteboard:
Crash report or crash signature: Regression By:

Description Peter Ryan 2020-11-13 00:06:38 UTC 
Description:
When I create a table and set the border line style to "Dotted", pressing Tab to step through table cells and then create new table rows, LO-Writer becomes increasingly slow and unusable.

Changing the border line style back to "Solid", or to "None" works around the problem. I've not tried all the line styles, but certainly "Dotted" and "Dashed" exhibited this problem.

Steps to Reproduce:
1. Start LibreOffice Writer
2. Insert a table - I use the tool-bar icon, and insert (say) 4 x 4, but I don't think size is particularly part of the problem
3. Right click the table and choose Table Properties...
4. Click the Borders tab, change the Line Style to "dotted" (it's the second one down, underneath the default "solid"), and click OK to close the Table Properties dialog
5. With the cursor in any of the table cells, press tab. Keep pressing tab until it starts adding new rows - cursor movement will slow and a CPU core will be running at/near 100%

Actual Results:
LO-Writer becomes increasingly slow as Tab is pressed and table rows are added.

Expected Results:
Should perform the same as with border line style None or Solid which work perfectly.


Reproducible: Always


User Profile Reset: Yes


OpenGL enabled: Yes

Additional Info:
About LibreOffice says:
"
Version: 6.4.6.2
Build ID: 1:6.4.6-0ubuntu0.20.04.1
CPU threads: 4; OS: Linux 5.4; UI render: default; VCL: gtk3; 
Locale: en-GB (en_GB.UTF-8); UI-Language: en-GB
Calc: threaded
"

I'm running Linux Mint Cinnamon 20 (64-bit) on an old Core i5 with 8GB RAM and nVidia GT1030 GPU.

I originally posted the issue here (along with a bunch of system-config info in case it's useful):
https://forums.linuxmint.com/viewtopic.php?f=47&t=334928
Comment 1 Dieter 2021-05-27 04:59:43 UTC 
I can't confirm the problem with

Version: 7.1.4.1 (x64) / LibreOffice Community
Build ID: f67b1ddedeb24fca1c5938e7cebfab73d708b35b
CPU threads: 4; OS: Windows 10.0 Build 19043; UI render: Skia/Raster; VCL: win
Locale: de-DE (de_DE); UI: en-GB
Calc: CL

Peter, could you please try to reproduce it with the latest version of LibreOffice from https://www.libreoffice.org/download/libreoffice-fresh/ ? I have set the bug's status to 'NEEDINFO'. Please change it back to 'UNCONFIRMED' if the bug is still present in the latest version. Change to RESOLVED WORKSFORME, if the problem went away.
Comment 2 Peter Ryan 2021-05-28 16:37:07 UTC 
Hi Dieter,
Thanks for checking this. I've tried it now on the same computer, so it's not the latest build but it has had a minor version bump from before and it is now working perfectly!

About LibreOffice says:
"
Version: 6.4.7.2
Build ID: 1:6.4.7-0ubuntu0.20.04.1
CPU threads: 4; OS: Linux 5.4; UI render: default; VCL: gtk3; 
Locale: en-GB (en_GB.UTF-8); UI-Language: en-GB
Calc: threaded
"

Thanks again! :D