Freezing tasks via the cgroup freezer causes the load average to climb because the freezer's current implementation puts frozen tasks in uninterruptible sleep (D state). Some applications which perform job-scheduling functions consult the load average when making decisions. If a cgroup is frozen, the load average does not provide a useful measure of the system's utilization to such applications. This is especially inconvenient if the job scheduler employs the cgroup freezer as a mechanism for preempting low priority jobs. Contrast this with using SIGSTOP for the same purpose: the stopped tasks do not count toward system load. Change task_contributes_to_load() to return false if the task is frozen. This results in /proc/loadavg behavior that better meets users' expectations. Signed-off-by: Nathan Lynch <ntl@pobox.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Nigel Cunningham <nigel@tuxonice.net> Tested-by: Nigel Cunningham <nigel@tuxonice.net> Cc: <stable@kernel.org> Cc: containers@lists.linux-foundation.org Cc: linux-pm@lists.linux-foundation.org Cc: Matt Helsley <matthltc@us.ibm.com> LKML-Reference: <20090408194512.47a99b95@manatee.lan> Signed-off-by: Ingo Molnar <mingo@elte.hu> |
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acpi | ||
asm-arm | ||
asm-frv | ||
asm-generic | ||
asm-h8300 | ||
asm-m32r | ||
asm-mn10300 | ||
crypto | ||
drm | ||
keys | ||
linux | ||
math-emu | ||
media | ||
mtd | ||
net | ||
pcmcia | ||
rdma | ||
rxrpc | ||
scsi | ||
sound | ||
trace | ||
video | ||
xen | ||
Kbuild |