Unix & Linux
tmux byobu
Updated Mon, 30 May 2022 11:51:25 GMT

tmux consuming 100% of cpu

I've been running byobu for a while now, and in the last few hours it has started to consume 30-100% of the CPU on the core it's running on. This a noticeable delay when entering text, or switching windows.

It does not appear to be an issue with the server (i've included the output of top below). Total memory and cpu usage appears fine, and if I open a new byobu session on the server it works fine (consuming almost 0% of the CPU).

I've never experienced this before. Any advice on what is causing it, and how to fix it without killing the whole session would be appreciated!

top - 16:09:40 up 93 days,  1:59,  4 users,  load average: 42.87, 42.77, 42.78
Tasks: 792 total,  48 running, 656 sleeping,   0 stopped,  88 zombie
Cpu(s): 38.3%us, 22.4%sy,  0.0%ni, 39.2%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
Mem:  528381020k total, 514696248k used, 13684772k free,    13172k buffers
Swap: 536855548k total, 114819772k used, 422035776k free,   501060k cached
  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND                                                                                                                                                                       
66004 scottr-u  20   0 88932  23m  888 S   52  0.0 270:36.19 tmux     


It's possible that there's a runaway status script from Byobu that's consuming all of the CPU. You can perhaps disable them one by one until you find the culprit. The updates_available script is probably the most resource intensive, and the one that causes this sort of trouble most often. If you do find which one is misbehaving, please file a bug at https://bugs.launchpad.net/byobu.

Full disclosure: I am the author and maintainer of Byobu.

Comments (3)

  • +0 – After logging back in this morning it seems to be behaving, CPU usage at <10%. If I see it happen again I'll try disabling some status notifications! — Nov 06, 2013 at 23:31  
  • +0 – Wouldn't it be a good idea to find out what version of Byobu @Manetheran is running, especially since there are known bugs (like bugs.launchpad.net/ubuntu/+source/byobu/+bug/1010505 ) that can cause this issue? — Nov 20, 2013 at 05:59  
  • +0 – Byobu version: 5.17 Tmux version: 1.6 I haven't had the issue replicate since (still the same byobu session open). — Nov 20, 2013 at 12:22  

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