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Subject: Re: [QUESTION] Performance deterioration caused by commit
 85f726a35e504418
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Yang Jihong <yangjihong1@huawei.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
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From:   "Zanussi, Tom" <tom.zanussi@linux.intel.com>
Message-ID: <ea059f74-95d8-3e33-fbeb-02ef1ac567b0@linux.intel.com>
Date:   Tue, 19 Oct 2021 13:38:37 -0500
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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.

Tom

> 
> -- Steve
>