Re: scale up (postgresql vs mssql)

On Wed, Apr 18, 2012 at 2:32 AM, Eyal Wilde <eyal(at)impactsoft(dot)co(dot)il> wrote:
> hi all,
>
> i ran vmstat during the test :
>
> [yb(at)centos08 ~]$ vmstat 1 15
> procs -----------memory---------- ---swap-- -----io---- --system--
> -----cpu-----
>  r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id
> wa st
>  0  0      0 6131400 160556 1115792    0    0     1    12   22   17  0  0
> 100  0  0
>  0  0      0 6131124 160556 1115800    0    0     0   532  540  360  1  0 99
>  0  0
>  5  1      0 6127852 160556 1116048    0    0     0  3352 1613 1162 18  1 80
>  1  0
>  7  0      0 6122984 160556 1117312    0    0     0 14608 5408 3703 86  7  6
>  1  0
>  8  0      0 6121372 160556 1117968    0    0     0 13424 5434 3741 86  7  5
>  2  0
>  7  1      0 6120504 160556 1118952    0    0     0 13616 5296 3546 86  7  5
>  2  0
>  7  0      0 6119528 160572 1119728    0    0     0 13836 5494 3597 86  7  4
>  2  0
>  6  1      0 6118744 160572 1120408    0    0     0 15296 5552 3869 89  8  3
>  1  0
>  2  0      0 6118620 160572 1120288    0    0     0 13792 4548 3054 63  6 25
>  6  0
>  0  0      0 6118620 160572 1120392    0    0     0  3552 1090  716  8  1 88
>  3  0
>  0  0      0 6118736 160572 1120392    0    0     0  1136  787  498  1  0 98
>  1  0
>  0  0      0 6118868 160580 1120400    0    0     0    28  348  324  1  0 99
>  0  0
>  0  0      0 6118992 160580 1120440    0    0     0   380  405  347  1  0 99
>  1  0
>  0  0      0 6118868 160580 1120440    0    0     0  1544  468  320  1  0
> 100  0  0
>  0  0      0 6118720 160580 1120440    0    0     0     0  382  335  0  0 99
>  0  0
>
>
> the temp-tables normally don't populate more then 10 rows. they are being
> created in advanced. we don't drop them, we use ON COMMIT DELETE ROWS. i
> believe temp-tables are in the RAM, so no disk-i/o, right? and also: no
> writing to the system catalogs, right?
>
> about returning multiple refcursors, we checked this issue in the past, and
> we concluded that returning many small refcursors (all have the same
> structure), is faster than returning 1 big refcursor. dose it sound wired
> (maybe it worth more tests)?  that's why we took that path.

no chance of seeing the code or a reasonable reproduction?

merlin