Re: Move unused buffers to freelist

>> Instead, I suggest modifying BgBufferSync, specifically this part right
>> here:
>>
>>         else if (buffer_state & BUF_REUSABLE)
>>             reusable_buffers++;
>>
>> What I would suggest is that if the BUF_REUSABLE flag is set here, use
>> that as the trigger to do StrategyMoveBufferToFreeListEnd().
>
> I think at this point also we need to lock buffer header to check refcount
> and usage_count before moving to freelist, or do you think it is not
> required?

If BUF_REUSABLE is set, that means we just did exactly what you're
saying.  Why do it twice?

-- 
Robert Haas
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