LibreOffice can max-out a CPU core

[pryan]

Hi all,

I've been using Linux Mint 20 for about a month now and generally, it's great! However, I did need to create a quick document in LibreOffice Writer recently and hit an issue that caused it to become unusably slow. To recreate:

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... then marvel at how slow it all becomes!

Turns out if you change the table borders to "None" or "Solid", then everything works fine. I've not tested all the other line styles, but "dashed" also exhibited the same CPU-core-maxing issue.

I'm using Linux Mint 20 (64-bit) on an old Core i5 with 8GB RAM and an nVidia GT1030 card:

Code: Select all

System:    Kernel: 5.4.0-53-generic x86_64 bits: 64 compiler: gcc v: 9.3.0 Desktop: Cinnamon 4.6.7 
           wm: muffin 4.6.3 dm: LightDM 1.30.0 Distro: Linux Mint 20 Ulyana base: Ubuntu 20.04 focal 
Machine:   Type: Desktop Mobo: ASUSTeK model: P7P55D v: Rev 1.xx serial: <filter> BIOS: American Megatrends 
           v: 2101 date: 10/20/2011 
CPU:       Topology: Quad Core model: Intel Core i5 750 bits: 64 type: MCP arch: Nehalem rev: 5 L2 cache: 8192 KiB 
           flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 21400 
           Speed: 1234 MHz min/max: 1200/2668 MHz boost: enabled Core speeds (MHz): 1: 1204 2: 1204 3: 1204 
           4: 1204 
Graphics:  Device-1: NVIDIA GP108 [GeForce GT 1030] vendor: Micro-Star MSI driver: nvidia v: 450.80.02 
           bus ID: 01:00.0 chip ID: 10de:1d01 
           Display: x11 server: X.Org 1.20.8 driver: nvidia unloaded: fbdev,modesetting,nouveau,vesa 
           resolution: 1920x1080~60Hz 
           OpenGL: renderer: GeForce GT 1030/PCIe/SSE2 v: 4.6.0 NVIDIA 450.80.02 direct render: Yes 
Audio:     Device-1: Intel 5 Series/3400 Series High Definition Audio vendor: ASUSTeK driver: snd_hda_intel 
           v: kernel bus ID: 00:1b.0 chip ID: 8086:3b56 
           Device-2: NVIDIA GP108 High Definition Audio vendor: Micro-Star MSI driver: snd_hda_intel v: kernel 
           bus ID: 01:00.1 chip ID: 10de:0fb8 
           Sound Server: ALSA v: k5.4.0-53-generic 
Network:   Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet vendor: ASUSTeK M4A785/P7P55 
           driver: r8169 v: kernel port: c800 bus ID: 02:00.0 chip ID: 10ec:8168 
           IF: enp2s0 state: up speed: 1000 Mbps duplex: full mac: <filter> 
Drives:    Local Storage: total: 2.27 TiB used: 1016.08 GiB (43.6%) 
           ID-1: /dev/sda vendor: Crucial model: CT500MX500SSD1 size: 465.76 GiB speed: 3.0 Gb/s serial: <filter> 
           rev: 023 scheme: MBR 
           ID-2: /dev/sdb vendor: Western Digital model: WD20EZRZ-00Z5HB0 size: 1.82 TiB speed: 3.0 Gb/s 
           rotation: 5400 rpm serial: <filter> rev: 0A80 scheme: MBR 
Partition: ID-1: / size: 54.75 GiB used: 13.50 GiB (24.7%) fs: ext4 dev: /dev/sda1 
           ID-2: /home size: 402.45 GiB used: 44.49 GiB (11.1%) fs: ext4 dev: /dev/sda2 
Sensors:   System Temperatures: cpu: 39.0 C mobo: N/A gpu: nvidia temp: 38 C 
           Fan Speeds (RPM): N/A gpu: nvidia fan: 35% 
Repos:     No active apt repos in: /etc/apt/sources.list 
           Active apt repos in: /etc/apt/sources.list.d/google-chrome.list 
           1: deb [arch=amd64] http://dl.google.com/linux/chrome/deb/ stable main
           Active apt repos in: /etc/apt/sources.list.d/official-package-repositories.list 
           1: deb http://www.mirrorservice.org/sites/packages.linuxmint.com/packages ulyana main upstream import backport
           2: deb http://archive.ubuntu.com/ubuntu focal main restricted universe multiverse
           3: deb http://archive.ubuntu.com/ubuntu focal-updates main restricted universe multiverse
           4: deb http://archive.ubuntu.com/ubuntu focal-backports main restricted universe multiverse
           5: deb http://security.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
           6: deb http://archive.canonical.com/ubuntu/ focal partner
Info:      Processes: 260 Uptime: 7h 08m Memory: 7.77 GiB used: 1.99 GiB (25.6%) Init: systemd v: 245 runlevel: 5 
           Compilers: gcc: 9.3.0 alt: 9 Shell: bash v: 5.0.17 running in: gnome-terminal inxi: 3.0.38

I can well imagine this is an issue with upstream... but I'm never sure where to report LibreOffice problems.

I've got a work-around in changing the table style, so this isn't super critical to me, but it probably could use being fixed though!

Cheers,

Peter.

[antikythera]

Have you turned off java in LO Options>Advanced? Sometimes that helps reduce the overhead and speed the office suite up for certain functions. I've not noticed it do what you describe but if you want to try reporting the bug you can do so here

[pryan]

Funny enough, yes I did that just prior to posting here. it didn't change help though!

Thanks for the link - I've filed a bug report: https://bugs.documentfoundation.org/sho ... ?id=138175