Dell Poweredge 2950 with PERC 5/i RAID

[Claudio Nasuti]

Hi All,
I just installed RHEL 4 U4 on a PowerEdge 2950
configured as follow:
a xeon 5150
two gigabytes of ram
six internal disks, 300 gigabyte SAS 10.000 rpm, factory configured in a single raid 5 container

The installation went smooth like a breeze but when I made a small IO test I have been shocked 
IO seems very poor as everyone can figure by numbers
[root at adm-sdf1 ~]# time dd if=/dev/zero of=./DummyFile bs=65536 count=65536
65536+0 records in
65536+0 records out

real    1m49.236s
user    0m0.032s
sys     0m8.348s

I repeated the same test several times but the result is more or less the same.
Do you have any suggestion ? Am I making something wrong?

Thanks,
Claudio
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