[CentOS] software raid

[chrism at imntv.com]

Feizhou wrote:
> William Warren wrote:
>> as soon as you goto software raid 5 you'll get a good performance 
>> hit. Head for the hardware raid cards then.  You can get the 3ware 
>> ide cards for 150 or less now.
>
> don't know if it is still the case but ext3 + 3ware + ext3 = ultra 
> slow. you'd want to use XFS or some other filesystem...

I keep hearing about this "slowness" thing.  Here is a bonnie++ run on 
one of my spare machines.  This particular machine is also running 4 
copies of Folding at Home in the background during the test.  The array 
being tested is on a 3Ware 9550 card with 8 500gig barracudas.  The 
filesystem is a standard ext3 filesystem with zero tweaks.  It doesn't 
appear that slow to me, but perhaps I'm just easy to please.

[ritz at localhost data]$ df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                      73575592   2868764  66909020   5% /
/dev/hda1               101086     16078     79789  17% /boot
/dev/sda1            3844873244 561019948 3088544960  16% /data
tmpfs                  1035584         0   1035584   0% /dev/shm
[ritz at localhost data]$ whereis bonnie++
bonnie++: /usr/sbin/bonnie++ /usr/share/man/man8/bonnie++.8.gz
[ritz at localhost data]$ clear
[ritz at localhost data]$ df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                      73575592   2868764  66909020   5% /
/dev/hda1               101086     16078     79789  17% /boot
/dev/sda1            3844873244 561019948 3088544960  16% /data
tmpfs                  1035584         0   1035584   0% /dev/shm
[ritz at localhost data]$ /usr/sbin/bonnie++ -f
Writing intelligently...done
Rewriting...done
Reading intelligently...done
start 'em...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...done.
Create files in random order...done.
Stat files in random order...done.
Delete files in random order...done.
Version  1.03       ------Sequential Output------ --Sequential Input- 
--Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- 
--Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  
/sec %CP
localhost.locald 4G           203807  96 169178  65           392171  63 
611.2   2
                    ------Sequential Create------ --------Random 
Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- 
-Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  
/sec %CP
                 16 +++++ +++ +++++ +++ +++++ +++ +++++ +++ +++++ +++ 
+++++ +++
localhost.localdomain,4G,,,203807,96,169178,65,,,392171,63,611.2,2,16,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++,+++++,+++