[openib-general] Re: RDMA memory registration

[David Addison]

Greg Lindahl wrote:
> On Fri, Apr 29, 2005 at 12:33:54PM -0700, Grant Grundler wrote:
> 
>>Being mostly clueless about Quadrics implementation, I'm probably
>>missing something that makes Quadrics a MMU but not the IB variants.
>>Can someone clue me in please?
> 
> As far as I can tell it's mostly a marketing distinction. Many
> Quadrics customers run with memory registration, and Mellanox could
> probably alter their firmware to not require registration.  Myricom
> certainly can, and in fact Patrick Geoffrey claimed they were doing so
> in their MX software. The only one I know of that isn't that flexible
> is PathScale's InfiniPath. Ours is a pure hardware mechanism, but it
> requires memory registration and is clearly not an MMU.
> 
Greg,
only a few of our evaluation customers use the patch free (and hence
page-pinning) software release.

Most do apply our simple IOPROC patch and run without requiring page
pinning whilst still achieving the peak bandwidth and low latency
of our hardware.

Cheers
Addy.