Re: linux distro for better pg performance

>I am searching for best pg distro to run pg (7.4.1).
>
>
This is generally based upon opinion. Honestly though, your kernel
version is more important for performance than the distro. Personally I
use gentoo, love gentoo, and would recommend very few other distros
(Slackware) for servers. RedHat and others seem to include
kitchensinkd, when it's not needed.

>At the moment I am using RedHat AS 3.0, but I think it have some
>performance problems (I am not sure).
>My configuration:
>P4 2.8 GHz
>1 GB RAM
>120 GB IDE 7200 disk.
>
>
Your IDE drive is the biggest hardward bottleneck here. RPM's and bus
transfers are slower than SCSI or SATA.

>Kernel version 2.4.21-4.EL (it is the installation vesrion for rh 3.0) .
>
>
Jump to 2.6, it's much better for performance related issues, in my
experience.

>My problems:
>
>If I run some query with many reads, I see a massive disk transfer :
>procs memory swap io
>system cpu
> r b swpd free buff cache si so bi bo in cs us sy
>id wa
> 0 0 0 261724 3252 670748 0 0 0 4 105 19 0 0
>100 0
> 0 0 0 261724 3252 670748 0 0 0 0 101 11 0 0
>100 0
> 0 0 0 261724 3260 670748 0 0 0 4 104 19 0 0
>100 0
> 0 1 0 259684 3268 674112 0 0 964 7 131 57 0 0
>95 4
> 1 0 0 119408 3288 808540 0 0 27960 0 572 630 13 14
>24 49
> 1 1 0 15896 3292 914436 0 0 7984 44744 531 275 11 18
>24 47
> 0 2 0 16292 3296 924996 0 0 4145 6413 384 176 2
>5 0 92
> 0 1 0 19928 3316 928844 0 0 11805 13335 497 388 5
>9 5 81
> 0 3 0 19124 3296 924452 0 0 3153 19164 287 295 5 11
>16 68
> 0 1 0 15956 3304 932984 0 0 536 6812 366 123 4
>6 3 87
> 0 2 0 24956 3300 921416 0 0 1931 22936
>
>And if I run top, I see a big iowait % (some times 70-80) and very low
>user % (10-15).
>
>
again, this is your harddrive, and the kernel can play into that.

>I readet many docs about this problem, but do not find any solution.
>
>My question:
>
>If some one is using RH 3.0, pls post some result or suggestions for it
>performance with pg .
>
>What is the best linux distro for pg?
>
>
There's no best, just personal preference.

>Can I get better performance by using 15K SCSI disk ?
>
>
Absolutely

>Or it will be better to have more RAM (2 or 3 GB) ?
>
>
Better to have a fast drive, but more ram can be helpful.

>regards,
>ivan.
>
>
>
HTH,

Gavin