Re: [PATCH 4/4]percpu_counter: use atomic64 for counter

From: Tejun Heo
Date: Tue Apr 12 2011 - 23:11:42 EST


On Wed, Apr 13, 2011 at 09:17:08AM +0800, Shaohua Li wrote:
> yes, we do have something this matters. the vm_committed_as
> percpu_counter could heavily contend the lock. please see
> We should fix vm_committed_as, but the atomic method also gives me very
> good output. When I do mmap/munmap test in a 24 CPU system, the atomic
> method gives me 50x faster.

That's good to hear. Care to provide the performance info in the
commit message too?


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at