On 09/06/2013 08:11 AM, Karli Sjöberg wrote:
What about swap? Don´t they have any swap file, or partition at all? Swap-file over NFS must suck quite badly, no? We have bought semi-cheap SSD's for our Hosts to use as swap to get more out of them from memory overprovisioning.
I don't quite see the point, unless you have mirrored ssd's. Data corruption on ssd's is more frequent than on spinning disks and disastrous when it happens in a swapped out page... (And why not add more RAM?)
But why use swap at all? I'm assuming you dimension a node to its intended use, so I guess lots of memory and CPU cores (in our case anyway) and you can allocate the available memory to the VMs until it's finished. I don't see much need for swap there.
Perhaps my view is different than usual, I see swap as the gravelly escape roads on steep hills for trucks/cars who have failing breaks. It just reduces the damage in case of unexpected failures. Swap isn't something to use on a regular basis as cheep memory, as RAM is not that expensive anymore and magnitudes faster.
/Simon _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
