Dell Perc6i Raid Performance

[Philipp Schmid]

Hi,

I wonder about our 2950 perc6i raid performance, which seems to be  
very bad as I only get 38Mb/s during write tests.
on another machine 2950 with perc6i in raid 50, I get about 105MB/s.

Is this normal? Why is raid 50 faster than raid 10? 38.7 MB/s seem  
very slow to me. My IBM notebook is faster than that...


xen26:~#  time dd if=/dev/zero of=bigfile bs=1M count=1000 conv=fsync
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 27.0645 s, 38.7 MB/s

real	0m27.311s
user	0m0.000s
sys	0m2.648s


Our configuration looks like:
6x500gb 7.2k sata drivers in raid 10

xen26:~# uname -a
Linux xen26.netmonic.local 2.6.26-1-amd64 #1 SMP Sat Jan 10 17:57:00  
UTC 2009 x86_64 GNU/Linux
xen26:~# omreport storage vdisk controller=0
List of Virtual Disks on Controller PERC 6/i Integrated (Embedded)

Controller PERC 6/i Integrated (Embedded)
ID                  : 0
Status              : Ok
Name                : Virtual Disk 0
State               : Ready
Progress            : Not Applicable
Layout              : RAID-10
Size                : 1,395.75 GB (1498675150848 bytes)
Device Name         : /dev/sda
Type                : SAS
Read Policy         : No Read Ahead
Write Policy        : Write Back
Cache Policy        : Not Applicable
Stripe Element Size : 64 KB
Disk Cache Policy   : Disabled


Lg Philipp