Bug 113104 - MacOS: CPU utilization while scrolling through a plain text document is around 90% on Retina HiDPI screens
Summary: MacOS: CPU utilization while scrolling through a plain text document is aroun...
Status: NEW
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: Writer (show other bugs)
(earliest affected) release
Hardware: All Mac OS X (All)
: high major
Assignee: Not Assigned
Keywords: perf
: 120545 121408 123283 (view as bug list)
Depends on:
Blocks: HiDPI MacOS-Performance
  Show dependency treegraph
Reported: 2017-10-13 18:45 UTC by Telesto
Modified: 2019-03-20 18:35 UTC (History)
8 users (show)

See Also:
Crash report or crash signature:

Screenshot Instruments (472.97 KB, image/png)
2017-12-31 10:26 UTC, Telesto

Note You need to log in before you can comment on or make changes to this bug.
Description Telesto 2017-10-13 18:45:38 UTC
CPU utilization while scrolling through a document is around 90%. Should probably be around 15% or so

Steps to Reproduce:
1. Open the attachment 135838 [details] (or any random file)
2. Scroll down while monitoring CPU usage (or using Instruments time profiler)

Actual Results:  
CPU utilization is around 90%

Expected Results:
Between 5 - 15% - similar to Windows or Linux - instead of 90% would be nice for a longer battery life

Reproducible: Always

User Profile Reset: No

Additional Info:
Build ID: 4d94541a7b88b76d856e30dba7f8a3de48260eda
CPU threads: 4; OS: Mac OS X 10.12.6; UI render: default; 
TinderBox: MacOSX-x86_64@49-TDF, Branch:master, Time: 2017-10-08_02:51:19
Locale: nl-NL (nl_NL.UTF-8); Calc: group

and in

User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0
Comment 1 Alex Thurgood 2017-10-16 09:55:17 UTC
Hmm, can't reproduce this reliably with:

Build ID: 75539963e621faafdc0d3ef6759cadb2e0a5d9b4
CPU threads: 8; OS: Mac OS X 10.12.6; UI render: default; 
Locale: fr-FR (fr_FR.UTF-8); Calc: group

At the beginning, processeur usage does indeed climb and stay quite high on my MBPro i7 16Mb RAM, but it drops off after a while even as I scroll through the document with the arrow key and stabilizes at between 15-30%.
Comment 2 Xisco Faulí 2017-12-27 07:27:55 UTC
Hi Telesto,
Is this issue still reproducible in master?
Comment 3 Telesto 2017-12-31 10:26:39 UTC
Created attachment 138762 [details]
Screenshot Instruments

(In reply to Xisco Faulí from comment #2)
> Hi Telesto,
> Is this issue still reproducible in master?

The issue still exists with a touchpad (didn't test a mouse). Everything is working smooth, but it's CPU hogging. Only scrolling a empty writer/calc document is enough. It looks suboptimal to me..
Comment 4 shara valery 2018-09-07 07:13:39 UTC Comment hidden (spam)
Comment 5 Taylor Joe 2018-10-16 12:45:34 UTC Comment hidden (spam)
Comment 6 Alex Thurgood 2018-11-14 12:05:54 UTC
*** Bug 121408 has been marked as a duplicate of this bug. ***
Comment 7 Martin Jungowski 2018-11-28 19:55:55 UTC
All these bugs about LibreOffice user interface sluggishness under macOS are related. LibreOffice performance in macOS is horribly abysmal, and that's the nicest way I can put this without getting kicked off the internet for good.

The problem seems to lie somewhere in the way LibreOffice draws its user interface. On high-resolution Retina displays LibreOffice is so slow that you can't even scroll down an EMPTY (!!!) Writer document or an EMPTY (!!!) spreadsheet smoothly. No way, no how. Scrolling is so jumpy and laggy. When moving objects in Draw, such as text boxes, embedded images, forms, etc. the entire UI seems to choke up and lags behind by more than 1-2 seconds. Resizing an image in a Draw document is practically impossible as it takes anywhere between 2-10 seconds for screen contents to update to reflect the new size.

Starting LibreOffice in Low Resolution improves performance noticeably but in return makes the entire application appear blurry, so that's not a solution either.

This has been going on for YEARS now. I can't tell how long for sure but definitely since the early days of LibreOffice somewhere around Version 4.x. LibreOffice under macOS is unusable on every Mac released after 2012, because that is when Apple introduced their high-resolution Retina display. It is now late 2018, we have 6-core MacBook Pros and 18-core iMac Pros and LibreOffice remains completely unusable under macOS on all of these. In fact, performance is so bad I have resorted to using Microsoft Office for editing OpenDocument files because using LibreOffice to edit a simple spreadsheet or text document feels like getting punched repeatedly in the face. With a sledgehammer. Swung by Thor. On Speed.
Comment 8 Alex Thurgood 2019-02-11 08:30:37 UTC
*** Bug 123283 has been marked as a duplicate of this bug. ***
Comment 9 Alex Thurgood 2019-02-11 08:36:17 UTC
*** Bug 120545 has been marked as a duplicate of this bug. ***
Comment 10 mitja 2019-02-25 14:15:10 UTC
I agree with the comments before.
Using LibreOffice on macOS and retina displays is terribly slow.
Consumes large amount of CPU, hardware acceleration is greyed out, etc.
It is actually not possible to do a normal work on a 5K display, even though you have a new iMac.
Please, take this "bug" seriously and put a priority on it.
I'm currently using LO 6.1.5 on iMac 5K.
Comment 11 Telesto 2019-02-25 16:13:05 UTC
FWIW: the (scrolling) performance of LibreOffice on Retina screen (comment 6-10) appears to be laggy.
Comment 12 Fabio 2019-03-08 16:57:37 UTC
With version 6.2 the bug has not been fixed.