Quoting r. Sean Hefty <[EMAIL PROTECTED]>: > Subject: Re: [PATCH for-2.6.18] Re: [PATCH] IB/cma: add rdma_establish > > Michael S. Tsirkin wrote: > > What I think we need for 2.6.18 is the following. Pls comment. > > > > > > IB/cma: increase the retry count in CMA from 3 to maximum 15. > > 3 seems low - we see connections failing under stress - and in any case > > looks > > like an arbitrary number. 15 is the max value allowed by spec. > > > > Signed-off-by: Michael S. Tsirkin <[EMAIL PROTECTED]> > > Dropping 3 packets in a row seems likely only under stress testing, so I'm > not > sure that this is worthy of a change to 2.6.18 at this point (we're at rc7).
I don't really understand. The fix is a one-liner. The problem is observed in practice, under stress. Who *wants* systems that fall apart under stress? It seems that with retry of 3, chances of losing one out of 3 packets would be close to 100% if loss rate is about 10%. Ranking it up to 15, you need loss rate on top of 50% to get close to 100% chance of losing connection request. Losing a DREP is also bad - as it leaves stale connections around munching up resources. So why aren't we fixing this? -- MST _______________________________________________ openib-general mailing list [email protected] http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
