2008-03-13 15:21:54

by Alexey Dobriyan

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Subject: Not so fair group scheduling

Simple testcase:

a) 2 physical CPUs, not HT or something
b) root gets 1024 cpu_share according to /sys/kernel/uids/0/cpu-chare
c) user gets 1024 cpu_chare --//--

root runs 1 busy loop, user runs 2 busy loops
According to top they got 57% for root, and 66+77% for user. But they
should have 100%/50+50% division. Am I right?

If yes are there any patches to fix this available for testing?