MarkusB (4/22/2010)
SQLGuru,thanks for your reply and I totally agree with you that a lot of SAN implementations are not very well done.
Unfortunately I joined my current company just after they had implemented the NetApp storage. And can you believe it, they never did any performance test before moving all the data to the SAN.
Now we have endless discussions about what is acceptable performance vs. the "other advantages" of having data on the SAN.
But while performance is not great, at the moment I have bigger worries with Iscsi errors while doing backups to a share on the SAN.
Lots of EventID 20 "Connection to the target was lost. The initiator will attempt to retry the connection." messages.
But looking at the bright side of things, these might finally convince management, that they made the wrong choice.
I would actually have been surprised if the company had done ANY perf testing prior to implementation!!
Have you ensured that every piece of hardware in the system has the latests certified drivers/firmware? It is AMAZING how many problems go away when you get those things addressed. Also review the network utilization metrics - some NICs/switches don't do very well if you start to saturate them. NIC teaming can be problematic if you don't dot the i's and cross the t's correctly. Oh, and have you checked for TCP/IP Chimney being enabled - BAD stuff there
I very rarely make this explicit suggestion (as opposed to a generic "hire a professional" recommendation) but please drop me a line if you feel as I do that a hired-gun would be helpful to give your environment and systems a performance review. I do this for a living and I doubt you have anything going on there that I haven't seen time and time again. 😎
Best,
Kevin G. Boles
SQL Server Consultant
SQL MVP 2007-2012
TheSQLGuru on googles mail service