How do I test disk performance in Freebsd60 ?

[Halid Faith]

I use FreeBSD60 on Dell1600 SC ( 2gbyte Ram 4 CPU )
amr0: <LSILogic MegaRAID 1.51> mem 0xfcc00000-0xfcc0ffff irq 21 at device
2.0 on pci2
amr0: <LSILogic PERC 4/SC> Firmware 351X, BIOS 1.10, 64MB RAM

I have 3 scsi disks that each about 70 Gbyte based RAID5. That is Total
capacity nearly 140 Gbyte.


I want to test disk / raid card.

I tried below command 10 times while I 'm root
date && dd if=/dev/zero of=deleteme.now bs=64k count=300 && rm deleteme.now
&& date

1 - 19660800 bytes transferred in 3.420916 secs (5747232 bytes/sec)
2 - 19660800 bytes transferred in 3.318186 secs (5925165 bytes/sec)
3 - 19660800 bytes transferred in 1.325308 secs (14834893 bytes/sec)
4 - 19660800 bytes transferred in 1.475633 secs (13323637 bytes/sec)
5 - 19660800 bytes transferred in 1.458992 secs (13475605 bytes/sec)
6 - 19660800 bytes transferred in 1.373914 secs (14310066 bytes/sec)
7 - 19660800 bytes transferred in 1.597467 secs (19307485 bytes/sec)
8 - 19660800 bytes transferred in 1.308806 secs (15021937 bytes/sec)
9 - 19660800 bytes transferred in 1.324031 secs (14849201 bytes/sec)
10- 19660800 bytes transferred in 1.438717 secs (13665510 bytes/sec)

As you see the values of  bytes/sec is not stable  very changeable.
I wonder Do disks or the raid card work properly ?

Thanks