A6826A Fiber channel slower disk IO then A6795A

[Luk Vandenbussche]

Hi,

We have to server with the same application and same disk setup.
Server 1 : rp5470 with dual A6795A fiber controller
Server 2 : rp4440 with dual A6826A fiber HBA.
Both the servers are connected a different DS2405, the Logical volumes are the same and the speed off the DS2405 is 2 GB.

But the disk IO on the rp4440 is 3 times slower then on the rp5470.

We installed the latest driver B.11.11.05 for the card A6826A on the rp4440.

What can you do the speed up the IO on the rp4440?

[RAC_1]

Is the firmware same?? Are the disks set exactly the same way??

[Luk Vandenbussche]

I'am 100 % sure that the disk setup is the same. We double checked it with three persons.
Which firmware? How can I check it

[Zeev Schultz]

Post output of "fcmsutil /dev/tdX" (where X is the number 0,1... get from output of 'ioscan -fnCfc') for both a6795a and a6826a.

a6826a is a dual port.both ports behave the same?

It requires certain patches (see below) :
-11.11
PHKL_28984 or later (required for fcmsutil)
PHKL_28569 or later (WSIO, not required if on HWE0306 or later)
PHKL_29468 or later (required for OLA/R support)
PHKL_28695 or later (VM, recommended for better performance)

[Mahesh Kumar Malik]

Hi

1. Check switch setting on LCC Card of DS2405 connected through A6826A. Data Transmission SW should be set to 2Gb Mode.

2. If LED on A6826A is Orange, it is communicating 1Gb speed, if Green speed is 2Gb

Regards
Mahesh

[Luk Vandenbussche]

The speed is 2 GB (see above)
I am waiting for the output off the requested commands

[Zeev Schultz]

Both fcmsutil /dev/tdX (fro a6826a) and ds2405 show 2Gbit/sec (can also check DS2405 via "cstm" , "sel dev" to line where "A6250A" appears and "info" , "il") ?

Did you verify that cables are ok? Could also see from fcmsutil /dev/tdX stat - check "Link fails", "loss of signal".

[Stuart Abramson]

EMC recommends that we set a kernel parameter, which I forget right now, but it's something like "max_scsi_disk_queue_depth". Could that be it?

[Luk Vandenbussche]

Here is the requested info

[Luk Vandenbussche]

2nd file