Hi there
I am sv-motioning from one iSCSI datastore to another (vCenter4 and ESX3.5U4 currently. I have not tried with ESX4 yet).
The operation is causing massive loads on the internal redhat5.3 server (e.g., 300+). Although I can still SSH in and ping it might as well be down. My question is why!
SV motion works fine on turned off guest VMs
The network link to the SANs is only at 7.5% capacity (2 x PS5000X From Equallogic). Flow control is enabled.
VM Tools are fully updated and working
The SV motion is purring along and it will finish eventually
This happens to us -sometimes- right after a vmotion attempt, where loads run away to ridiculous levels for up to 15 minutes.
VMWare support (at least the level 1 team I've spoken to) has never been able to resolve/understand the query to solve it. Any help would be greatly appreciated 
I'm running another test hot sv-motion now. (I gave it another 1GB of RAM). Swapping is firmly on 0. The VM itself seems fragile, if I sneeze load
seems to climb
Could the VM be starved of I/O bandwidth to the shared storage perhaps, causing the load to climb? That is the only other thing I can think of.
Currently I have it set up as follows, now that I think of it the svmotion and the SAN traffic may be potentially contended over the one link;
VMKernel. vmotion - enabled
=Active Adapters=
vmnic0
vmnic3
vmnic4
vmnic5
Should I have something like this instead?
VMKernel
vmotion - disabled
Active: vmnic 0, vmnic4
VMKernel2
vmotion - enabled
Active: vmnic 3, vmnic5
If so:
i) Can they be on the same vswitch, or should they be separated, or does it not matter?
ii) How do I ensure that only vmotion traffic goes over VMKernel2, and not iSCSI general traffic? I know I can check 'use this port group for Vmotion', but I would obviously like to isolate only iscsi traffic on VMKernel and only vmotion traffic on VMKernel2.
iii) I assume that svmotion and vmotion traffic are functionally the same thing when setting up the ports.
Thanks for all your assistance.