CERC Performance Question

[Sturgis, Grant]

Can anyone comment if these numbers look normal or not?

Thanks.

Sturgis, Grant wrote:
> Greetings List,
> 
> I am experiencing very poor performance with a CERC SATA 1.5/6ch RAID 
> card wtih firmware v4.1-0.  Four disks are configured in RAID 5 and the 
> OS is RHEL ES 4.0.  I understand that this is not a high performance 
> RAID card or RAID configuration (write penalty associated with RAID 5), 
> but this just seems ridiculous.
> 
> Created a 5GB file with the command:
> 
> dd if=/dev/zero of=big_file bs=1024 count=5120000
> 
> and then timed a move operation from an NFS mount to the local RAID 
> array connected at 1000Mbps end-to-end:
> 
> time mv /hosts/server/test/big_file local_test_folder
> 
> and the results were:
> 
> 0.623u 34.342s 9:44.65 5.9%     0+0k 0+0io 3pf+0w
> 
> This is over 10 minutes to move that much data over a gigabit 
> connection.  What's even worse is that the load average on the system 
> exceeded 18 resulting in an unusable system for all other users.  There 
> was no response to any commands or login attempts.
> 
> Does this seem reasonable to you?  What can I do to improve this 
> performance (short of doing away with RAID 5)?
> 
> Any comments and suggestions are very much appreciated.
> 
> Thanks,
> 
> Grant
> ----------------
> 
> 
> 
> 
> Pardon this rubbish:
> 


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