[ofa-general] Performance of MT25204 versus MT25208

[Chuck Hartley]

It turns out that SuperMicro recently released a BIOS update for our
motherboards.  No release notes to say what all was done, but after
installing the update we now have MaxReadReq = 4096.  I ran ib_rdma_bw and
now we are getting 1500MB/s instead of 1336.



On Jan 21, 2008 4:14 AM, Bart Van Assche <bart.vanassche at gmail.com> wrote:

> 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.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openfabrics.org/pipermail/general/attachments/20080121/bb7baeb0/attachment.html>