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FC disks performance problem

Alberto Tagliaferri
Occasional Contributor

FC disks performance problem

I'm having performance problems on several of my hp-ux boxes accesing EMCs arrays (SAN FC-AL). Without any identified change, I/O performance on fs. over EMC disks has become poor.
I'd like to find out if the problem is on the disk arrarys, SAN or UX box. Can I use "fcmsutil stat" info to help with this? Anyone could guide on what to look at?

Thanks in advance,
Alexander M. Ermes
Honored Contributor

Re: FC disks performance problem

Hi Alberto.
Use the sar command to collect data and then find the bottleneck.

# sar
0 * * * * /usr/lbin/sa/sa1
20,40 * * * * /usr/lbin/sa/sa1
5 23 * * * /usr/lbin/sa/sa2 -s 00:00 -e 23:59 -i 900 -A

Alexander M. Ermes
.. and all these memories are going to vanish like tears in the rain! final words from Rutger Hauer in "Blade Runner"
Ovidiu D. Raita
Valued Contributor

Re: FC disks performance problem

A month ago a coworker of mine faced performance degradation of his FC access to EMC box.

Resolution .... Guess what ?

The EMC support eng enabled tracing on all the disks without telling and forgot to disable them. It took them 4 days to return back to normal. Some time sh.. happens.

It was just a thought :)

You might have a bad EMC disk of fibre. Better change the fibers if you can and ask then ask EMC support for help.

Happy New Year,
Simple solutions to complex problems