Strange behaviour of UFS2+SU FS on FreeBSD 8-Stable: dreadful perofrmance for old data, excellent for new.

[Ivan Voras]

On 27.8.2011. 9:21, Lev Serebryakov wrote:

>    I'm going to investigate alter, why it is ony ~180MiB/s, when
> theoretically it should be about (90*4) 360MiB/s linear read, and whom
> to blame: UFS or geom_raid5 or both :)

Try this: http://ivoras.net/blog/tree/2010-11-19.ufs-read-ahead.html

(or it could be a hardware issue - controller bottleneck or something 
like that).