I have issues with RPC latency spiking when I perform a VSS full backup. The issue is only occurring during the backup and when it occurs it prevents users from receiving email. On the user end, during this time mail being sent is slow but still occurs. On the server end, mail is stuck in the queue for the mailbox database and sends mail through very slowly. I ran a scheduled performance monitor 15 minutes prior to the backup and it lasts for one hour. I have captured the spike in RPC Latency/Disk Activity.
This server has been in production before, without this issue, but this time we added a new storage controller. Before, we were using an on-board storage controller. I also have a near identical system that had no issues at all.
