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List:       pgsql-hackers
Subject:    Re: [HACKERS] Optimizing numeric SUM() aggregate
From:       Andrew Borodin <borodin () octonica ! com>
Date:       2016-07-29 12:44:14
Message-ID: CAJEAwVEjAjQs4etk5qAyzrcNHV2c=fdrEUqkTgYcRHTFAejcDQ () mail ! gmail ! com
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I've tested patch with this query
https://gist.github.com/x4m/fee16ed1a55217528f036983d88771b4
Test specs were: Ubuntu 14 LTS VM, dynamic RAM, hypervisor Windows
Server 2016, SSD disk, core i5-2500. Configuration: out of the box
master make.

On 10 test runs timing of select statement: AVG 3739.8 ms, STD  435.4193
With patch applied (as is) : 3017.8 ms, STD 319.893

Increase of overflow const showed no statistically viable performance
improvement (though, I do not worth doing).

2016-07-27 17:32 GMT+05:00 Tom Lane <tgl@sss.pgh.pa.us>:
> For that matter, spelling INT_MAX as 0x7FFFFFF is also not per project style.

Sure, 0x7FFFFFF was not for code but for metal arithmetics. I would
even add that INT_MAX is system-dependent and varies in different
specs. I'd suggest INT32_MAX.

Best regards, Andrey Borodin, Octonica & Ural Federal University.


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