Re: Relation extension scalability

On 17/03/16 04:42, Dilip Kumar wrote:
>
> On Mon, Mar 14, 2016 at 8:26 AM, Petr Jelinek <petr@2ndquadrant.com
> <mailto:petr@2ndquadrant.com>> wrote:
>
>     Well any value we choose will be very arbitrary. If we look at it
>     from the point of maximum absolute disk space we allocate for
>     relation at once, the 4MB limit would represent 2.5 orders of
>     magnitude change. That sounds like enough for one release cycle, I
>     think we can further tune it if the need arises in next one. (with
>     my love for round numbers I would have suggested 8MB as that's 3
>     orders of magnitude, but I am fine with 4MB as well)
>
>
> I have modified the patch, this contains the max limit on extra pages,
> 512(4MB) pages is the max limit.
>
> I have measured the performance also and that looks equally good.
>

Great.

Just small notational thing, maybe this would be simpler?:
extraBlocks = Min(512, lockWaiters * 20);

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