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Subject: Re: [QUESTION] Performance deterioration caused by commit
 85f726a35e504418
To:     "Zanussi, Tom" <tom.zanussi@linux.intel.com>,
        Steven Rostedt <rostedt@goodmis.org>
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From:   Yang Jihong <yangjihong1@huawei.com>
Message-ID: <9d0844e4-271e-41f7-3883-3dd1e572a8c8@huawei.com>
Date:   Wed, 20 Oct 2021 10:00:28 +0800
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Hi, Steve and Tom

On 2021/10/20 2:38, Zanussi, Tom wrote:
> On 10/19/2021 1:10 PM, Steven Rostedt wrote:
>> On Tue, 19 Oct 2021 12:30:28 -0500
>> "Zanussi, Tom" <tom.zanussi@linux.intel.com> wrote:
>>
>>> So anyway, as far as the histograms go, I think optimizing the two
>>> changes in 85f726a35e504418 while ignoring trailing garbage can be done
>>> without affecting the histogram correctness.
>>
>> So, none of that is exported to user space?
> 
> I meant just that any optimization of those two things that ignored the
> trailing garbage wouldn't affect the histogram keys.
> 
> But yeah I think you're correct that ignoring it in the case of
> saved_cmdlines wouldn't be a problem either but it would be in the case of
> max_buffer since that's exported by the ring buffer.

OK. Thanks very much for your patience. :)

Kind regards,
Jihong
> 
> Tom
> 
>>
>> -- Steve
>>
> .