T620 - Horribly Slow

Hi Guys,

I've been hitting my head of the wall from the past few weeks dealing with dell support, so I figured I'd through it out to the community to see if there's some wise person out there, that can help.

Basically I have 5 servers on customer sites, carbon copies of each other. (Specs Below)

T620

32GB RAM

E5-2620v2 - Hex with HT

Raid 5 H710 512 Cache

4x 300GB SAS 15K

iDRAC7 Express

Server 2012 R2 Pre-installed by dell.

Each server runs two VM's DC/DB IIS.

No A/V on host, iscsi target for backup connected in the VM.

Basically the problem is that the server starts to crawl at a horrible speed, pinging between the VMs goes to 100+ms. Even with the VM's turned off the server(host) still crawls. Opening Hyper-v manager 30+ seconds.

Here's the "funny part" rebooting the server doesn't resolve the issue but turn the server (host) off for 30 seconds and boom its all good again.

Could be fine for a week or a month after the reboot, I'm thinking it might be something to do with a cache on the RAID card with queues filling up or something like that.

Any Ideas?