[Linux-cluster] Slowness above 500 RRDs

[Ferenc Wagner]

Hi,

I installed the new OpenAIS infrastructure (cluster-2.00.00) on my
cluster.  Here are the results of the usual tests:

== Using PLOCKS ==
filecount=500
  iteration=0 elapsed time=10.294059 s
  iteration=1 elapsed time=9.416584 s
  iteration=2 elapsed time=10.30608 s
  iteration=3 elapsed time=10.294692 s
  iteration=4 elapsed time=10.280316 s
total elapsed time=50.591731 s
filecount=501
  iteration=0 elapsed time=11.170378 s
  iteration=1 elapsed time=10.312731 s
  iteration=2 elapsed time=10.308767 s
  iteration=3 elapsed time=10.308905 s
  iteration=4 elapsed time=10.308703 s
total elapsed time=52.409484 s

== Using FLOCKS ==
filecount=500
  iteration=0 elapsed time=5.311825 s
  iteration=1 elapsed time=7.030903 s
  iteration=2 elapsed time=5.23619 s
  iteration=3 elapsed time=5.229282 s
  iteration=4 elapsed time=5.235798 s
total elapsed time=28.043998 s
filecount=501
  iteration=0 elapsed time=5.03941 s
  iteration=1 elapsed time=5.278866 s
  iteration=2 elapsed time=4.93929 s
  iteration=3 elapsed time=5.271063 s
  iteration=4 elapsed time=5.133244 s
total elapsed time=25.661873 s

The magic limit of 500 disappeared, and flocks are indeed twice as
fast as plocks, something you probably expected.  However, in the
first test the old infrastructure was much-much faster, doing an
iteration in about 0.2 s, thanks to some caching effect.  This is the
kind of performance I'm after.  How can I tune the new infrastructure,
like cache sizes in the old?  Or should I look for something else?
-- 
Thanks,
Feri.