I'm running a game-server on my Gentoo VDS, but it's not scheduling the thread ids properly. This appears to be causing a bottleneck on the main core which leads to performance issues. Attached bellow is the process and all the thread ids which belong to it. I would like to place the thread id which matches the process id on core 0 and all the other threads on core 1. Any help as to how to go about doing this would be appreciated. I don't want to upgrade to more threads just for one server.
rna1 ~ # top
top - 14:08:47 up 4 days, 21:34, 1 user, load average: 1.02, 1.00, 0.96
Tasks: 78 total, 2 running, 76 sleeping, 0 stopped, 0 zombie
%Cpu(s): 46.2 us, 2.2 sy, 0.0 ni, 43.2 id, 0.3 wa, 0.0 hi, 8.1 si, 0.0 st
KiB Mem: 2051032 total, 2032372 used, 18660 free, 316300 buffers
KiB Swap: 4194300 total, 2068 used, 4192232 free. 1116472 cached Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
4840 stickz 20 0 502392 303760 27272 R 95.5 14.8 1607:32 srcds_linux
rna1 ~ # ps -p 4840 -L -o pid,tid,psr,pcpu
PID TID PSR %CPU
4840 4840 1 67.1
4840 4842 0 0.0
4840 4844 0 0.0
4840 4847 1 0.0
4840 4850 0 0.0
4840 4852 1 0.4
4840 4855 1 0.0
4840 4861 1 0.0
4840 4862 1 0.0
4840 5192 1 0.0
Setting TID Affinity
Re: Setting TID Affinity
Manually assigning threads to specific cores usually is not a good idea, but you can do it with "taskset".
To see the CPU usage for each thread in "top", press "H" while it is running.
To see the CPU usage for each thread in "top", press "H" while it is running.
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stickz
Re: Setting TID Affinity
Taskset worked and all my performance issues just went away after scheduling the two gameplay threads on separate cores. I find it quite odd how the CPU usage is dramatically lower now as-well, with higher players count.
The stall time went from 0.0 to 0.3 which means one of my physical cores is being shared with someone else.
The stall time went from 0.0 to 0.3 which means one of my physical cores is being shared with someone else.
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stickz
Re: Setting TID Affinity
Wait a minute, could this have given myself full control over a physical core, by activating both threads? The CPU usage is too low to use more than one physical core.
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stickz
Re: Setting TID Affinity
Or was the issue having hyperthreading disabled with approximately six query threads? Everything would essentially be dumped on a single physical core massively increasing the CPU usage. That explains the zero stall time beforehand and having 0.3 afterwards. http://forums.nfoservers.com/viewtopic.php?f=47&t=5099