Which controller on the ML? From: Bill Songstad [mailto:[email protected]] Sent: Wednesday, April 06, 2011 1:20 PM To: NT System Admin Issues Subject: OT: VMware disk latency
I have an ESXi4 setup on a HP ML350 G5 running a RAID5 array of sata drives for the primary datastore and a drobo iscsi array for the secondary datastore. 2 VMs on each datastore. 4 VMs total. All w2k8. When I do a large file copy to any of the VMs from a share on a different physical machine there is huge latency, and not just on the machines hosted on the drobo. Okay, not the fastest disk arrays in the world, but I wonder if my bottleneck is elsewhere though. Durring the file copy, latency on the physical disks shoots up to 200-500 Milliseconds. But on the Virtual disks, the latency is literally 10 times that, with the other machine on that datastore essentially mirroring the physical disk. Subsequently, the machines effectively stop responding. Durring a file copy to vm1 the latencies look like this: Physical DAS latency 300 ms vm1 vdisk on DAS latency 3,000 ms vm2 vdisk on DAS latency 300 ms Physical iSCSI latency 0 ms vm3 vdisk latency 0 ms vm4 vdisk latency 0 ms Is this to be expected? Why the ten-fold discrepancy between the actual disk and the virtual disk? Any insights would be appreciated, -Bill ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to [email protected]<mailto:[email protected]> with the body: unsubscribe ntsysadmin ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to [email protected] with the body: unsubscribe ntsysadmin
