For those of you that have enabled ODX on your EqualLogic arrays, what speeds are you seeing? i'm a little disappointed so far - I'm only seeing about 200MB/s. Here is my configuration:
Server
Dell R310
Latest BIOS
Onboard BCM5716C (2 ports)
HP 331T (4 Port) – two of these ports are used for iSCSI traffic
Switches
2 HP ProCurve 2910al, latest BIOS
Each switch is 1gb, 24 ports
VLAN 109 is set to Untagged for the iSCSI ports on both switches
Jumbo Frames is enabled on the iSCSI ports
Software flow control is enabled on the iSCSI ports
10GB interconnect backplane between switches
SAN
PS6100XS, 6.0.2 firmware (latest)
I'm testing by simply using Windows Explorer to copy at 45GB file. If I disable ODX by running the following in PowerShell:
I get speeds of 110MB/s and the transfer takes 410 seconds
With ODX enabled, I get average speeds of about 240MB/s and it takes 200 seconds (3 mins 20 seconds).
Don't get me wrong, that's a big improvement, but articles like this one http://i.dell.com/sites/doccontent/business/solutions/whitepapers/en/Documents/microsoft-offloaded-data-transfer-equallogic.pdf led me to expect closer to 400MB/s speeds with ODX.
There are obviously other major benefits with ODX such as the near-zero network and CPU utilization, but I'm curious - what speeds are you seeing in your environment?
So during an ODX copy, the SAN is still actually doing the same work in the same way as a non-ODX transfer? For some reason I had thought that during an ODX transfer it was actually just essentially updating pointers to the data.
I was expecting a lot higher. ODX disabled resulted in around 97.6mb/sec so whilst we saw a big improvement using ODX, it's still a far cry from Dell's own results.
Keep in mind that their speeds are on a 10gb network with a 10gb SAN. While the speed boost is nice, what's really nice about ODX is the near-zero draw on the network and cpu utilization during the transfer, which would otherwise saturate your network and cause substantial cpu load.
Im seeing similar results on a single PS6100E array. However, my non-ODX file copies are about 200MBs whereas my ODX file copies are about 175MBs. I have another storage group with 2 PS6100XV (faster SAS drives) and the performance is even worse within the pool or cross pool (the switching network may be the limiting factor here).
jakesterpdx
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Posted March 7th, 2013 09:00
So during an ODX copy, the SAN is still actually doing the same work in the same way as a non-ODX transfer? For some reason I had thought that during an ODX transfer it was actually just essentially updating pointers to the data.