Hi, out of curiosity, are you using encryption and hmac or simple messaging? Fabio On 5/23/2012 4:28 PM, Voznesensky Vladimir wrote: > Hello. > > I've tested Corosync latency without IPC. > > First, I've found a Pload module and instrumented it's data > messages with TSC values, so become able to measure CPU ticks > spending in the Corosync stack for each message. Second, I've > measured the average ticks to pass 300 bytes messages in different > batch sizes with and without Totem on a single node. Totem > disabling was carried out in accordance to the "[PATCH] Example > short-circuit of totem for single node cases - for TESTING ONLY" > message of 18 May from this maillist. > > bindnetaddr: 127.0.0.1 hold: 0 > > I have run corosync with the CPU affinity set to a single > hyper-thread to prevent the process from loosing cache and context > switching, though it does not help a lot: the results are stable > for 10000 and 100000 only. > > # taskset 0x1 /usr/sbin/corosync -f > > > The latency (in ticks)/throughput(in TP/S) for each variant: > > batch size| with Totem | w/o Totem 1 | 596K/5.4M | > 58K/5M 10 | 0.8M/1.9M | 82K/3M 100 | 5.0M/1.2M | > 5M/0.9M 1000 | 7.9M/1.4M | 8M/1.3M 10000 | 24.4M/2.0M | > 23M/2.1M 100000 | 31.8M/1.2M | 31M/1.3M > > There is a strong gap in latencies for 1 and 10 message batches: > some of the cases are small (tens kiloticks), and some of them are > big (millions ticks). I have no explanation. > > The latency seems to not depend on the totem realization, but looks > very high. Am I doing something wrong? > > Thanks. > > -- VV _______________________________________________ discuss > mailing list discuss@xxxxxxxxxxxx > http://lists.corosync.org/mailman/listinfo/discuss _______________________________________________ discuss mailing list discuss@xxxxxxxxxxxx http://lists.corosync.org/mailman/listinfo/discuss
