DSS on VM hosted on ESX 4.1 Slow Performance

[habibalby]

Hi,

I have DSS installed on a Virtual Machine running under ESX 4.1. 200 GB VMDK is presented via the ESX DataStore. 1 Target and 2 Vol Group created and presented to the ESX as an iSCSI Target. Formatted as VMFS and hosted 1 Windows 2k3 VM. I tested copying file locally inside the VM is very slow and gives me speed of 2.3 or 1.8 MB/s. Wherein if I move this VM locally to the same ESX Datastore and start to copy files locally I get 35 ~ 48 MB/s.

DSS is installed with 3 GB memory and 2 vCPUs.

What could be the issue and how can I achieve high read and writes?

Thanks,

[Al-S]

What is your build of DSS that you are using?

It could be that you need some tuning, try :

maxRecvDataSegmentLen=262144
MaxBurstLength=16776192
Maxxmitdatasegment=262144
FirstBurstLength=65536
DataDigest=None
maxoutstandingr2t=8
InitialR2T=No
ImmediateData=Yes
headerDigest=None
Wthreads=8

Also to change the Jumbo frame:
http://kb.open-e.com/Does-Open-E-sup...Frames_28.html

This changes should be made to each target.

Try also to check your initiator settings, even if you have to remove all settings and create them again.

[habibalby]

hello,

I'm using 6.0up50.8401.4786 32bit. I have tried these settings as I have found them in one of the thread in this forum. But nothing helps. Jumbo frames enabled in the ESX vSwitch. I will try the jumbo frame on the DSS site and let you know..

Thanks,

[Gr-R]

hello,

I'm using 6.0up50.8401.4786 32bit. I have tried these settings as I have found them in one of the thread in this forum. But nothing helps. Jumbo frames enabled in the ESX vSwitch. I will try the jumbo frame on the DSS site and let you know..

Thanks,

for jumbo frames to work, it must be enable along the entire path.

[habibalby]

Hi,
I have enabled it and rebooted the DSS, still same issue. Copy started at 5.5 MB/s and ended up on 1.7 MB/s

[To-M]

Can you test with the latest version and select 64bit mode instead of 32bit?

[habibalby]

I will try that.. Thanks for this suggestion. will reply to you once it's done..

[habibalby]

Hello,
I have tried that, it gives same problem.. Today I'm going to try NFS on windows 2008 32bit and compare the performance.

Any suggestion, please feel free..
Thanks,

[To-M]

On the ESX server where the DSS V6 is installed what is the system RAID settings to be sure that the ESX is tuned for Write cache and other settings.