I’ll set the scene a little…
I’m working late, I’ve just installed Update Manager and I‘m going to run my first updates. Like all new systems, I’m not always confident so I decided “Out of hours” would be the best time to try.
I hit “Remediate” on my first Host then sat back, cup of tea in hand and watch to see what happens….The Host’s VM’s were slowly migrated off 2 at a time onto other Hosts.
“It’s gonna be a long night” I thought to myself. So whilst I was going through my Hosts one at time, I also fired up Google and tried to find out if there was anyway I could speed up the VMotion process. There didn’t seem to be any article or blog posts (that I could find) about improving VMotion Performance so I created a new Servicedesk Job for myself to investigate this further.
3 months later whilst at a product review at VMware UK, I was chatting to their Inside Systems Engineer, *********, and I asked him if there was a way of increasing the amount of simultaneous VMotions from 2 to something more. He was unsure, so did a little digging and managed to find a little info that might be helpful and fired it across for me to test.
After a few hours of basic testing over the quiet Christmas period, I was able to increase the amount of simultaneous VMotions…Happy Days!!
But after some further testing it seemed as though the amount of simultaneous VMotions is actually set per Host. This means if I set my vCenter server to allow 6 VMotions, I then place 2 Hosts into maintenance mode at the same time, there would actually be 12 VMotions running simultaneously. This is certainly something you should consider when deciding how many VMotions you would like running at once
Found this over at Jason Boche’s blog. I’ts a guest post by Simon Long. It beats the heck out of a similar post I had in my drafts folder. Woo! Great work!