Re: REGRESSION: Performance regressions from switching anon_vma->lock to mutex
From: Tim Chen <hidden>
Date: 2011-06-15 18:42:46
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From: Tim Chen <hidden>
Date: 2011-06-15 18:42:46
Also in:
lkml
On Wed, 2011-06-15 at 18:45 +0200, Peter Zijlstra wrote:
On Wed, 2011-06-15 at 09:18 -0700, Andi Kleen wrote:quoted
And in general it looks like blind conversion from spinlock to mutex is a bad idea right now.For 4 socket machines, maybe. On 2 sockets I cannot reproduce anything. I wonder if its the fairness thing, the mutex spinners aren't fifo fair like the ticket locks are. It could be significant with larger socket count since their cacheline arbitration is more sucky.
Peter, Wonder if you can provide the profile on your run so I can compare with what I got on 4 sockets? Thanks. Tim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>