Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Tue, Nov 17, 2015 at 11:50:40PM -0500, Chuck Bredestege wrote: > I found this thread which is very close to the issue I am seeing: > http://lists.linbit.com/pipermail/drbd-user/2015-October/022484.html Is that so. And, did the patch I posted there help, or change behaviour in any way? > If I change the resource file to use 'ipv4' instead of 'sdp' it works just > fine. I get about 350MB/s throughput which is very low considering the > raid controller consistently gets about 900MB/s - but that's for a > different conversation. I would like to get the SDP protocol working since > the NPtcp benchmark from netpipe yields 2x the bandwidth and 1/2 the > latency as using TCP/IPoIB alone. (20GB/s and 3.1usec). > > > Again - SDP works in 8.3 without complaint - it's just slow. There is no reason to believe SDP would be "faster" with 8.4, even if it worked. It would still be the very same SDP. In my experience, DRBD + SDP does not help with throughput or latency, not really anyways. DRBD + tuned-for-DRBD SDP would only help to reduce CPU usage compared to IPoIB mode. > I saw the patch file at the end of the thread I linked above, > I applied it and there was no change. Too bad. > Any help would be greatly appreciated. Apparently SDP does not work in DRBD 8.4. I'm not aware of any customer trying to use it, either. The underlying problem is that at some point we changed from blocking accept() to using ->sk_state_change() callbacks. Which SDP does not implement. So we never notice that a connection is actually established, it will always appear to "time out". You could still change the first kernel accept into a blocking one, in the patch referenced above. - err = kernel_accept(ad->s_listen, &s_estab, O_NONBLOCK); + err = kernel_accept(ad->s_listen, &s_estab, 0); And hope that this does not block forever, and maybe even works similar to how it used to work with drbd 8.3. At least that should give you a starting point... -- : Lars Ellenberg : http://www.LINBIT.com | Your Way to High Availability : DRBD, Linux-HA and Pacemaker support and consulting DRBD® and LINBIT® are registered trademarks of LINBIT, Austria. __ please don't Cc me, but send to list -- I'm subscribed