Re: DREQ timeout for rdma-cm consumers

[Or Gerlitz <ogerlitz-smomgflXvOZWk0Htik3J/w@public.gmane.org>]

Sean Hefty wrote:
> I believe that the IB timeout of 20 is about 4 seconds.  If the packet lifetime is 1 second, then each try will take 6 seconds to timeout.  For 15 retries, this is close to 100 seconds.  
okay, thanks for explaining this.

> You should be able to destroy the rdma_cm_id at anytime
I understand that, however, currently the code I am working with (iser) 
wait to get both flushes on all the posted work requests AND disconnect 
or address-change event to mark the <rdmacm id, qp> couple as 
disconnected, clear it up and signal higher level to reconnect. I'll 
have to look what is the way to go for fast reconnection, maybe connect 
a new <id, qp> couple before the current one is totally 
flushed/disconnected. Also, destroying the ID doesn't remove the qpn 
from the IB CM timewait database, correct? hence if I don't wait long 
enough and the driver/hw reuses the qpn short enough to hit the IB CM 
stale connection/etc logic, I will not be able to reconnect, I guess.

Or.
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