fast after storage move

server 2012, clustered hyper v, 2 hosts , approx 15 guests on hp p2000 g3 san (dual controllers  2 x sas connections per host server)

 i experiencing confusing issue , hoping has suggestions.

we have rds farm 2 servers , have been getting bit slow respond.

i added 8 new 15k disks san, configured raid 10 , used 2 rds servers.

using crystal disk mark test speed on these 2 servers 1000mb/s on sequential reads.

a couple of days later down 80mb/s on testing.

the confusing part! if perform "move virtual storage operation" different virtual disk on same san, speed comes back.

if move original location speed 1000mb/s again.

this no users logged on, no backups running, nothing.

move out, , again (40 mins entire operation) , speed increases dramatically

i have both rds servers on same lun , 1 running @ 10 x speed of other.

it works either server, 1 move picks speed. 

thanks

james

hi leo, response.

i have dig through san config , see can find.

i can reproduce @ , have confirmed 3 more servers morning.

can opinion on couple of assumptions.

1)crystal disk running locally on server being tested therefore issues broadcom nics , vmq should not part of equation test not crossing nic?

2)i can produce behavior multiple vm's on multiple vdisks. 2 extremely similar vm's on same lun, either 1 can end running 10 x faster other or can both fast few days. me suggests more hyper v issue physical storage?

3)do sas connections negotiate connection speeds nic?

unfortunately san not have built in performance monitoring tool. 

i update san firmware , start case hp first before onto ms.

thanks

james

Windows Server  >  Hyper-V