[ofa-general] Performance of MT25204 versus MT25208

[Sagi Rotem]

Yes, this is the third option ;-)
but pay attention that this is a WA, u need to upgrade the BIOS in order
to get a stable system 

-----Original Message-----
From: Bart Van Assche [mailto:bart.vanassche at gmail.com] 
Sent: Monday, January 21, 2008 11:14 AM
To: Sagi Rotem
Cc: Openib-General; Chuck Hartley
Subject: Re: [ofa-general] Performance of MT25204 versus MT25208

On Jan 18, 2008 5:09 PM, Sagi Rotem <Sagir at mellanox.co.il> wrote:
> This may be your problem:
> MaxReadReq 128 bytes
> U need a BIOS update , common value with good performance is 512.
> Alternatively u can force it using setpci but than system may be 
> unstable.

After unloading and reloading the ib_mthca module with parameter
tune_pci=1 (which sets MaxReadReq to 4096,) ib_rdma_bw now reports a
bandwidth of 933 MB/s.

Thanks,

Bart.