Byobu + Tmux = High Load Average

Asked by Joe Pahl on 2012-11-13

I have been using Byobu and Tmux for a while now and all has been good. As far as I can remember I have never seen a load average over 0.5. Recently there was an update (not sure which one or what was changed and not sure how to look) but after that Byobu with Tmux now causes high load averages (I have seen up to 2 and 3) on an idle machine. The machine is a headless Ubuntu server with little to no traffic on it and I am the only user. I have read many postings on this issue and believe it is do to the system messages at the bottom of the byobu screen as when in quiet mode I get load averages of 0.04 0.07 0.10. I am not sure if this is a bug or not which is why I am only asking a question. Ubuntu 12.04 LTS.

I love byobu and tmux and would like to continue using them but the high load average makes me a little nervous. How do I fix this issue?

Thank you for your help in advance.

When I type byobu-quiet or byobu-quiet --undo I receive this message in response:
 $ byobu-quiet
tmux: unknown option -- X
usage: tmux [-28lquvV] [-c shell-command] [-f file] [-L socket-name]
            [-S socket-path] [command [flags]]

However it still switches byobu's messaging mode.

Things I have done:
I have completely uninstalled and purged byobu and tmux and reinstalled.
When byobu is set to use screen as its back end I see load averages of 0.00 0.09 and 0.10.
When I set byobu to use Tmux it once again goes back to the high load averages.

Information I am only guessing you will want:
This machine is a P4 with 1 gig ram and 1 80 gig hard drive with an extra mounted usb 250gb hard drive.

Top with tmux and byobu running (this was taken within 1 minute of running byobu):
top - 09:09:19 up 17:24, 1 user, load average: 1.05, 0.58, 0.29
Tasks: 94 total, 1 running, 93 sleeping, 0 stopped, 0 zombie
Cpu(s): 1.3%us, 1.3%sy, 0.0%ni, 97.4%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1024584k total, 944688k used, 79896k free, 281676k buffers
Swap: 1510072k total, 1080k used, 1508992k free, 436616k cached

 $ dpkg -l byobu
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Description
+++-======================================-======================================-============================================================================================
ii byobu 5.17-0ubuntu1 powerful, text based window manager and shell multiplexer

 $ dpkg -l tmux
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Description
+++-======================================-======================================-============================================================================================
ii tmux 1.6-1ubuntu1 terminal multiplexer

$ byobu -v
byobu version 5.17
Screen version 4.00.03jw4 (FAU) 2-May-06

$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 3
model name : Intel(R) Pentium(R) 4 CPU 3.00GHz
stepping : 4
microcode : 0x13
cpu MHz : 2992.302
cache size : 1024 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe constant_tsc pebs bts pni dtes64 monitor ds_cpl cid xtpr
bogomips : 5984.60
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:

processor : 1
vendor_id : GenuineIntel
cpu family : 15
model : 3
model name : Intel(R) Pentium(R) 4 CPU 3.00GHz
stepping : 4
microcode : 0x13
cpu MHz : 2992.302
cache size : 1024 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 1
apicid : 1
initial apicid : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes

cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe constant_tsc pebs bts pni dtes64 monitor ds_cpl cid xtpr
bogomips : 5985.46
clflush size : 64
cache_alignment : 128
address sizes : 36 bits physical, 32 bits virtual
power management:

Question information

Language:
English Edit question
Status:
Answered
For:
Ubuntu byobu Edit question
Assignee:
No assignee Edit question
Last query:
2012-11-13
Last reply:
2012-11-13

If you run it as another user, is it the same?

Joe Pahl (nophreak) said : #2

I just created another user (as there was no other user on the system) and as far as I can see it is still causing the high load average.

top - 09:26:59 up 5 min, 1 user, load average: 0.75, 0.60, 0.32
Tasks: 90 total, 1 running, 89 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.8%us, 1.8%sy, 0.0%ni, 97.3%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1024584k total, 251552k used, 773032k free, 7064k buffers
Swap: 1510072k total, 0k used, 1510072k free, 134864k cached

I also noticed while re-reading my post that the memory was full and the swap file was being used. This is not normal behavior for my machine. I rebooted my machine before creating the new user and printing out the above top average.

Two minutes later:

top - 09:29:06 up 7 min, 1 user, load average: 0.64, 0.63, 0.37
Tasks: 90 total, 1 running, 89 sleeping, 0 stopped, 0 zombie
Cpu(s): 0.3%us, 1.3%sy, 0.0%ni, 98.3%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1024584k total, 251560k used, 773024k free, 7064k buffers
Swap: 1510072k total, 0k used, 1510072k free, 134864k cached

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 3091 test 20 0 3756 1736 1200 S 1 0.2 0:01.15 tmux
    1 root 20 0 3520 1820 1272 S 0 0.2 0:01.01 init
    2 root 20 0 0 0 0 S 0 0.0 0:00.01 kthreadd
    3 root 20 0 0 0 0 S 0 0.0 0:00.04 ksoftirqd/0
    6 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/0
    7 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/0
    8 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/1
    9 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/1:0
   10 root 20 0 0 0 0 S 0 0.0 0:00.02 ksoftirqd/1
   11 root 20 0 0 0 0 S 0 0.0 0:00.12 kworker/0:1
   12 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/1
   13 root 0 -20 0 0 0 S 0 0.0 0:00.00 cpuset
   14 root 0 -20 0 0 0 S 0 0.0 0:00.00 khelper
   15 root 20 0 0 0 0 S 0 0.0 0:00.00 kdevtmpfs
   16 root 0 -20 0 0 0 S 0 0.0 0:00.00 netns
   18 root 20 0 0 0 0 S 0 0.0 0:00.00 sync_supers
   19 root 20 0 0 0 0 S 0 0.0 0:00.00 bdi-default
   20 root 0 -20 0 0 0 S 0 0.0 0:00.00 kintegrityd
   21 root 0 -20 0 0 0 S 0 0.0 0:00.00 kblockd
   22 root 0 -20 0 0 0 S 0 0.0 0:00.00 ata_sff
   23 root 20 0 0 0 0 S 0 0.0 0:00.00 khubd
   24 root 0 -20 0 0 0 S 0 0.0 0:00.00 md
   25 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/1:1
   26 root 20 0 0 0 0 S 0 0.0 0:00.00 khungtaskd
   27 root 20 0 0 0 0 S 0 0.0 0:00.00 kswapd0
   28 root 25 5 0 0 0 S 0 0.0 0:00.00 ksmd
   29 root 39 19 0 0 0 S 0 0.0 0:00.00 khugepaged
   30 root 20 0 0 0 0 S 0 0.0 0:00.00 fsnotify_mark
   31 root 20 0 0 0 0 S 0 0.0 0:00.00 ecryptfs-kthrea
   32 root 0 -20 0 0 0 S 0 0.0 0:00.00 crypto
   40 root 0 -20 0 0 0 S 0 0.0 0:00.00 kthrotld
   41 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/u:2
   42 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_0
   43 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_1
   44 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_2
   45 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_3
   46 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/u:3
   67 root 0 -20 0 0 0 S 0 0.0 0:00.00 devfreq_wq
   68 root 20 0 0 0 0 S 0 0.0 0:00.02 kworker/0:2
   73 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_4
   74 root 20 0 0 0 0 S 0 0.0 0:00.01 usb-storage
  116 root 20 0 0 0 0 S 0 0.0 0:00.58 kworker/1:2
  193 root 0 -20 0 0 0 S 0 0.0 0:00.00 ttm_swap
  235 root 20 0 0 0 0 S 0 0.0 0:00.02 kjournald
  300 root 20 0 2836 612 452 S 0 0.1 0:00.17 upstart-udev-br
  307 root 20 0 3108 1196 740 S 0 0.1 0:00.11 udevd

Joe Pahl (nophreak) said : #3

Just another top to hopefully get this solved and to show an example of what high load averages I am seeing:

top - 09:33:13 up 11 min, 1 user, load average: 2.00, 1.06, 0.58
Tasks: 89 total, 1 running, 88 sleeping, 0 stopped, 0 zombie
Cpu(s): 1.8%us, 1.2%sy, 0.0%ni, 97.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 1024584k total, 251768k used, 772816k free, 7096k buffers
Swap: 1510072k total, 0k used, 1510072k free, 134856k cached

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 3091 test 20 0 3756 1736 1200 S 1 0.2 0:02.69 tmux
    1 root 20 0 3520 1820 1272 S 0 0.2 0:01.01 init
    2 root 20 0 0 0 0 S 0 0.0 0:00.01 kthreadd
    3 root 20 0 0 0 0 S 0 0.0 0:00.04 ksoftirqd/0
    6 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/0
    7 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/0
    8 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/1
    9 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/1:0
   10 root 20 0 0 0 0 S 0 0.0 0:00.02 ksoftirqd/1
   11 root 20 0 0 0 0 S 0 0.0 0:00.14 kworker/0:1
   12 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/1
   13 root 0 -20 0 0 0 S 0 0.0 0:00.00 cpuset
   14 root 0 -20 0 0 0 S 0 0.0 0:00.00 khelper
   15 root 20 0 0 0 0 S 0 0.0 0:00.00 kdevtmpfs
   16 root 0 -20 0 0 0 S 0 0.0 0:00.00 netns
   18 root 20 0 0 0 0 S 0 0.0 0:00.00 sync_supers
   19 root 20 0 0 0 0 S 0 0.0 0:00.00 bdi-default
   20 root 0 -20 0 0 0 S 0 0.0 0:00.00 kintegrityd
   21 root 0 -20 0 0 0 S 0 0.0 0:00.00 kblockd
   22 root 0 -20 0 0 0 S 0 0.0 0:00.00 ata_sff
   23 root 20 0 0 0 0 S 0 0.0 0:00.00 khubd
   24 root 0 -20 0 0 0 S 0 0.0 0:00.00 md
   25 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/1:1
   26 root 20 0 0 0 0 S 0 0.0 0:00.00 khungtaskd
   27 root 20 0 0 0 0 S 0 0.0 0:00.00 kswapd0
   28 root 25 5 0 0 0 S 0 0.0 0:00.00 ksmd
   29 root 39 19 0 0 0 S 0 0.0 0:00.00 khugepaged
   30 root 20 0 0 0 0 S 0 0.0 0:00.00 fsnotify_mark
   31 root 20 0 0 0 0 S 0 0.0 0:00.00 ecryptfs-kthrea
   32 root 0 -20 0 0 0 S 0 0.0 0:00.00 crypto
   40 root 0 -20 0 0 0 S 0 0.0 0:00.00 kthrotld
   41 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/u:2
   42 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_0
   43 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_1
   44 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_2
   45 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_3
   46 root 20 0 0 0 0 S 0 0.0 0:00.00 kworker/u:3
   67 root 0 -20 0 0 0 S 0 0.0 0:00.00 devfreq_wq
   68 root 20 0 0 0 0 S 0 0.0 0:00.02 kworker/0:2
   73 root 20 0 0 0 0 S 0 0.0 0:00.00 scsi_eh_4
   74 root 20 0 0 0 0 S 0 0.0 0:00.01 usb-storage
  116 root 20 0 0 0 0 S 0 0.0 0:00.92 kworker/1:2
  193 root 0 -20 0 0 0 S 0 0.0 0:00.00 ttm_swap
  235 root 20 0 0 0 0 S 0 0.0 0:00.02 kjournald
  300 root 20 0 2836 612 452 S 0 0.1 0:00.17 upstart-udev-br
  307 root 20 0 3108 1196 740 S 0 0.1 0:00.11 udevd

Sounds like a bug then. The new user will have vanilla settings so the application is at fault.

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