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To:     Waiman Long <longman@redhat.com>,
        "Wang, Kemi" <kemi.wang@intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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From:   Tim Chen <tim.c.chen@linux.intel.com>
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Subject: Re: [LKP] [mm] 9bc8039e71: will-it-scale.per_thread_ops -64.1%
 regression
Message-ID: <907779d2-09a8-47fb-4d77-c907cd716b3c@linux.intel.com>
Date:   Wed, 30 Jan 2019 16:06:36 -0800
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On 12/27/18 6:55 PM, Waiman Long wrote:
> On 12/27/2018 08:31 PM, Wang, Kemi wrote:
>> Hi, Waiman
>>    Did you post that patch? Let's see if it helps.
> 
> I did post the patch a while ago. I will need to rebase it to a new
> baseline. Will do that in a week or 2.
> 
> -Longman
> 

Waiman,

In a large scale OLTP benchmark, we are also seeing a 1% loss in performance
from patch 9bc8039e71. We'll be interested to try out your patch to
restore some optimistic spinning on reader held sem.

Thanks.

Tim