Hack bench regression with CONFIG_SLUB_CPU_PARTIAL disabled (infoonly)

From: Raghavendra K T
Date: Thu Jul 25 2013 - 04:03:34 EST


Hi,

While testing hackbench with 3.11-rc1 I observed hackbench testcase
took too long to complete (32 vcpu kvm guest on 32 core HT off machine).

hackbench 1x degraded by 3 time (40sec vs 112sec)
hackbench 2x degraded by around 20time (90sec vs 1800 sec)

When I bisected, I found that I had CONFIG_SLUB_CPU_PARTIAL
accidentally disabled.
I understand that CONFIG_SLUB_CPU_PARTIAL=y by default and the config
option is to provide determinism for RT kernels and thus it is not a
problem.
But thought of sharing this here so that if somebody runs into same issue accidently, it would save their time.

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