Re: Fun little performance IMPROVEMENT... - Mailing list pgsql-performance

From grant@amadensor.com
Subject Re: Fun little performance IMPROVEMENT...
Date
Msg-id e4f4c267cceafee13c7ae455c7bf1ffc.squirrel@grant.boldlygoingnowhere.org
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In response to Re: Fun little performance IMPROVEMENT...  (Andy Colson <andy@squeakycode.net>)
List pgsql-performance
>
> Odd.  Did'ja by chance run the select more than once... maybe three or
> four times, and always get the same (or close) results?
>
> Is the stress package running niced?
>
The stress package is not running niced.  I ran it initially 5 times each.
  It was very consistent.  Initially, I just ran everything to files.
Later when I looked over it, I was confused, so tried it again, several
times on each, with very little deviation, and the process with the CPU
stressed always being faster.

The only deviation, which is understandable, was that the first run of
anything after memory stress (using 7G of the available 8G). was slow as
it swapped back in, so I did a swapoff/swapon to clear up swap, and still
got the same results.



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