From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Yang, Xiaowei" <xiaowei.yang@intel.com>
Subject: Re: [PATCH] use atomic_t type for system wide credit
	scheduler statistics
Date: Mon, 09 Mar 2009 16:30:39 +0800
Message-ID: <49B4D3AF.7050705@intel.com>
References: <C5DA7F2D.47D3%keir.fraser@eu.citrix.com>
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Keir Fraser wrote:
> Not while csched stats are enabled by default. They get cranked all over the
> place. How much does this race matter? We probably just lose a few
> increments?

Yes. The higher frequency the count is updated, the more increments lost 
can we see - comparing to atomic version, counts like "vcpu_check" and 
"scheduele" lose increments very obviously due to race.

Thanks,
xiaowei