2 thoughts on - How To Limit Cpu Usage For Specified Processes

• Hello,

  You could do it with Cgroups, if your specified processes run or can be made to run in group permissions.

  https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Resource_Management_Guide/sec-cpu_and_memory-use_case.html

  Regards,

• hello, In the past I mainly used blkio controller in control groups, to limit disk I/O bandwidth of a process. Just to notice that the cpu controller also has the cfs_quota_us and cfs_period_us which can provide absolute limits, in respect with relative ones of the shares parameter. In Red Hat manual I only see the shares parameter, but you can find more info about the other two installing kernel-doc package and reading
  /usr/share/doc/kernel-doc-2.6.32/Documentation/scheduler/sched-bwc.txt

  A rapid test on a CentOS 6.5 system with 2 physical cpus, 8 cores each and HT enabled

  yum install libcgroup

  service start cgconfig

  cgcreate -g cpu:/half_cpu

  echo “2000” > /cgroup/cpu/half_cpu/cpu.cfs_quota_us echo “4000” > /cgroup/cpu/half_cpu/cpu.cfs_period_us

  You can tune latency/burst working on period value… see the doc I use a program that makes matrix multiplication (1024×1024 in example below) and fully uses one cpu

  ./bmm 1024
  elapsed 10 seconds using top during execution I see line detail of this type around the 32
  threads:
  Cpu18 :100.0%us, 0.0%sy, 0.0%ni, 0.0%id, 0.0%wa, 0.0%hi, 0.0%si,
  0.0%st

  cgexec -g cpu:half_cpu ./bmm 1024
  elapsed 20 seconds using top I see line detail of this type during execution:
  Cpu0 : 49.8%us, 0.0%sy, 0.0%ni, 50.2%id, 0.0%wa, 0.0%hi, 0.0%si,
  0.0%st

  HIH, Gianluca