Correct. But multicast packets are droped at the QP receive level if the
app does not provide enough buffers to accept the data stream. The
bufers can easily be overrun if one does not code carefully given that
the maximum number of those is 16K or so. These drops occurs silently.
Currently
On Tue, 24 Nov 2015, Anuj Kalia wrote:
> InfiniBand flow control is done at the link layer, so UD does not drop
> packets due to congestion.
Correct. But multicast packets are droped at the QP receive level if the
app does not provide enough buffers to accept the data stream. The
bufers can
Thank you very much for the info, is there a good Infiniband reference
(other than the IBA spec, I mean) I should read?
-Peter
On 11/24/2015 05:08 PM, Anuj Kalia wrote:
I don't have experience with multicast, but here's some info.
InfiniBand flow control is done at the link layer, so UD does
On Wed, 25 Nov 2015, Peter Chinetti wrote:
> > Correct. But multicast packets are droped at the QP receive level if the
> > app does not provide enough buffers to accept the data stream. The
> > bufers can easily be overrun if one does not code carefully given that
> > the maximum number of those
I don't have experience with multicast, but here's some info.
InfiniBand flow control is done at the link layer, so UD does not drop
packets due to congestion.
AFAIK, UD only drops packets due to irrecoverable bit errors and
network device failures. Mellanox's FDR physical layer has BER less
I've been reading* through the IBA spec (Release 1.3 2015-03-03), trying
to understand IB multicast and its pitfalls.
I understand that IB multicast only supports Unreliable Datagram sends
(10.5.2.1), and that there are neither delivery guarantees nor
acknowledgments for UD sends.
