[ofw] [owf][patch] user multicast offload support

[Slava Strebkov]

Hi Fab, please read my answers

Slava

 

-----Original Message-----
From: Fab Tillier [mailto:ftillier at windows.microsoft.com] 
Sent: Tuesday, July 01, 2008 7:18 PM
To: Sean Hefty; Slava Strebkov; ofw at lists.openfabrics.org
Subject: RE: [ofw] [owf][patch] user multicast offload support

 

>>Voltaire has developed the LSP for Multicast Offload. Fast data path

>>will use this service provider working on IB using ibal.dll.

>>Original service provider TCP/IPoIB is using to transfer IGMP requests

>>to Ethernet routers which may be connected to IB host through IPR.

>>IB join will come from user mode and from IPoIB too. The common place

>>for them is in the ibal.lib.

>>To improve performance of HCA on receive path, IPoIB does not issue

>>ATTACH to the group which already attached from user mode by LSP.

> 

>This leads me back to my original suggestion of simply having a

>parameter on the join multicast group that indicates if the QP should
be

>attached.  This is way simpler and moves the complexity of determining

>when to attach to the ULP, where it belongs.

Multicast group opened from user mode is always attached. Attachment of
groups from IPoIB depends on whether same group was attached previously
from user mode. IPoIB does not know this.

 

Even better us to let the client apps use the existing
ib_join/leave_mcast functions and internally detect whether the SA MC
registration needs to be done or not, as well as reference counting the
SA MC registration.

Implementing this will require additional efforts; we'll consider this
later, in future releases.

 

Would you ever join a MC group without also attaching at least one QP?

Not yet

-Fab

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openfabrics.org/pipermail/ofw/attachments/20080702/bed956ae/attachment.html>