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I recently set up a server running Ubuntu 10.04 LTS on a Dell PowerEdge 2950 server - it has 6 500 gb 7200RPM SATA drives setup in a RAID 10 config.
I am seeing extremely poor disk performance - the RAID array reports all disks are normal and using MegaCLI, it looks like the BBU is fine.
hdparm -tT /dev/sda reports:
- Timing cached reads: 90 MB in 2.05 seconds = 43.96 MB/sec
- Timing buffered disk reads: 24 MB in 3.11 seconds = 7.72 MB/sec
So as you can see, it takes forever to something as simple as an apt-get upgrade and even logging into the server.
How do I go about troubleshooting what is causing this? I upgraded the firmware on the PERC 6i RAID controller to the latest, but didn't see any improvements.