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Date: Thu, 25 Jul 2013 13:30:17 +0530
From: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Organization: IBM
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CC: "David S. Miller" <davem@davemloft.net>,
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        Eric Dumazet <edumazet@google.com>, Al Viro <viro@zeniv.linux.org.uk>,
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Subject: Hack bench regression with CONFIG_SLUB_CPU_PARTIAL disabled (info
 only)
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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.