Greetings everyone :) My configuration is the following:
HP C3000 tower enclosure
1st HP Proliant BL460 G1 quad core xeon 2.66GHz 12MB L2 cache, 24GB RAM, BIOS I15 5/2/2011 partnered with HP SB40C Storage Server equipped with P400 Smart Array controller-256MB cache, firmware 7.24
2nd HP Proliant BL460 G1 quad core xeon 2.66GHz 12MB L2 cache, 24GB RAM, BIOS I15 5/2/2011 partnered with HP SB40C Storage Server equipped with P400 Smart Array controller-256MB cache, firmware 7.24
3rd HP Proliant BL460 G1 2 x dual core xeon 3.00GHz 8MB L2 cache, 16GB RAM, BIOS I15 5/2/2011 partnered with HP SB40C Storage Server equipped with P400 Smart Array controller-256MB cache, firmware 7.24
The SB40C servers are each populated with 6 samsung 250GB SSDs in a raid10 single partition array
BBWC is enabled on all 3 P400's
Installed respectively on each ProLiant is Xenserver 6.2 (free edition) with:
7 VMs on 1st proliant (4 x win2k3-r2, 1 x winxp, 2 x ubuntu) (thin provisioning enabled=ext3)
12 VMs on 2nd proliant (2 x win2k3-r2, 10 x winxp) (thin provisioning enabled=ext3)
8 VMs on 3rd proliant (2 x win2k3-r2, 10 x winxp) (thin provisioning disabled=LVM)
On the 2nd and 3rd proliant, it is a xendesktop 4 environment
Previously, the storage blades were populated each with 6 10k SAS and the average disk read/write speeds in the VMs were around 90/50 MBps. Now that SSDs are in place, Im benchmarking the VMs disks using Crystal Disk Mark 5 (couldnt get iometer to work for some reason), and the results after this upgrade come close to 260/200 MBps in most VMs. It varies a little from one to another depending on OS but they're all in the 200 MB range.
I need to know where should i start in troubleshooting since instead of having incredibly fast VMs they are actually somewhat laggy and im sure there is no network-related bottleneck. im beginning to suspect the vcpu side of the matter. I need someone to please point me in the right direction.
My questions:
1- Are the new disk speeds considered pretty good for a vm disk performance? and more importantly, enough to eliminate any disk related lagging?
2- Do I need to worry about fine-tuning the raid controller and read-ahead cache for xenserver like in this link? The settings are left to default (25-75% read-write, noop.. etc..)
3- since i dont need that much storage, isnt raid 10 the best way to go? (as opposed to 1, 0, 5, or 6?)
4- what would happen if take out the p400 and go with software raid instead? or even yet, no raid at all? (in regards of disk performance)
5- what about the hotfixes for XenServer 6.2? there are a bunch of updates available including SP1. would it help at all? im reluctant to apply them because i keep reading about hosts not starting afterwards.
6- is the quad core xeon enough for 12 VMs? should i enable more cores and assign 4 vcpus to the VMs as described in here?
I realize they are quite a few questions but any help is appreciated.
