I have a Dell PowerEdge R820 server which is under maintenance by other third party. There are 6 SAS (10K RPM, 6gbps) disks and they are configured as RAID 5 using PERC controller.
Currently I am facing performance issue with the server. Basically it is with the disk. When I tried to write 4GB of data, it is taking 12 minutes to complete. I am using a Linux Server.
Please see the output of dd command:
# # time dd if=/dev/zero of=TestFile bs=4096 count=1024000 1024000+0 records in 1024000+0 records out real 12m 3.56s user 0m 7.94s sys 0m 0.00s
I have also checked with the other Desktop made server, where RAID 5 is configured with 4 SATA (7.2K RPM) disks. It is taking only 19 seconds to write 4GB of data to the disk.
I can see the clear problem of disk I/O performance issue. But the third party is denying, they are telling that, this is the normal time. But I refuse to agree with them.
Can you please tell me what should be the normal time to write 4GB data to the volume configured with 6SAS (10K RPM) disks?