the performance of SAS is not better than SCSI in FreeBSD, WHY?

[Tzu-Hua Wang]

2007/4/11, Ivan Voras <ivoras at fer.hr>:
>
> Tzu-Hua Wang wrote:
> >    Hi:
> >
> >    Thank you for your response.
> >
> >    Ther performance of your server is significantly better than mine.
>
> Only in seek times, but this may be an artifact of RAID1. Do you use
> 2.5" or 3.5" disks?


2.5"

>    The SAS Chip of my HP ProLiant DL380 G5 is Smart HP Smart Array P400.
>
> Mine was E200i.
>
> >    It uses the FreeBSD driver ciss0
>
> Same here.
>
> >    I think that there is only one difference between your HP server and
> >    mine.
> >
> >    I configure my SAS HD as RAID 0.
> >
> >    Will this affect the performance?
>
> RAID should be much faster than RAID1 for the kind of tests diskinfo
> performs.
>
> Do you mean that RAID 0 perform better than RAID 1?
How about RAID 5?

Thank you