So we have a new HDS 110 running over to Nexus 5k's 10gb and down to 2k's coming out to the hosts at 1gb. The overall performance is ok (not FC but hey.. do what we can) After putting some file servers and a few exchange servers on the hosts, I have started to see some high latency messages. They are not severe right now, but as the company grows and more and more VM's are added, I can see this becoming an issue. Each of these file servers and exchange servers are on their own LUN coming off the HDS, so there should be no I/O contention among VM's at this point.
I'm not sure if there are some settings I have not set or if this latency is just a by-product of iSCSI. I am more of a FC guy so iSCSI is another world for me right now. I did set the disk.UseDeviceReset to 0 and disk.UseLunReset to 1. These are the only disk settings I have done for the host side. I was just reading a few things on some Dell MD3200's and they were taking about setting the "delayed ack" setting on the iSCSI adapter. I am wondering, should I be doing this for the host for my HDS as well?
Has anyone come across a specific "vmware tuning/config guide" for the host connecting to the Hitachi HDS platform? Anyone have any tips or pointers for this VMware / Storage setup?
Any advise would be appreciated.
Thanks
e~