Re: SLRU statistics

On Tue, Apr 07, 2020 at 05:01:37PM +0530, Kuntal Ghosh wrote:
>Hello Tomas,
>
>On Thu, Apr 2, 2020 at 5:59 PM Tomas Vondra
><tomas.vondra@2ndquadrant.com> wrote:
>> Thank you for the patch, pushed.
>>
>In SimpleLruReadPage_ReadOnly, we first try to find the SLRU page in
>shared buffer under shared lock, then conditionally visit
>SimpleLruReadPage if reading is necessary. IMHO, we should update
>hit_count if we can find the buffer in SimpleLruReadPage_ReadOnly
>directly. Am I missing something?
>
>Attached a patch for the same.
>

Yes, I think that's correct - without this we fail to account for
(possibly) a quite significant number of hits. Thanks for the report,
I'll get this pushed later today.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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