FreeBSD MySQL still WAY slower than Linux

[Mark Kirkwood]

Michael Schuh wrote:
> Hello,
> 
> yes random IO is more targetted to Databases.
> noop, i have the installation always made in the same way, and i have respected
> the different diskperformace in different disk-parts.....
> this was the reason for
> 
> #cd /; 
> 
> at the beginning of my tests.
> In the first test i have me shooting self in my foot and i bites me in
> my ass :-)))
>  

I was referring to the partitions and slices on the physical disk - each 
operating system is installed in a different one of these, and so is in 
a different physical part of the disk - hence you cannot reliably 
compare IO rates between them (This very issue has been discussed before 
I recall - try a Google search, as it is quite interesting).

> my suggestion going more in the direction...first solve all disk(ata) related
> performace issues, then test the mysql-performaces issues again to secure
> that you are not lying on an mixing of many problems.... :-)
> 

While noone would complain about faster sequential IO, it is almost 
certainly not the issue effecting database performance - for instance I 
find Postgresql consistently faster on RELENG_5 (5.3 onwards) than on 
RELENG_4 (using the pgbench program).

cheers

Mark