Profiler data with JBMAR r174
Galder Zamarreno wrote:
Hi David,
Please find attach graphs belonging to two runs that compare:
infinispan-4.0.0(repl-sync) - home grown marshalling layer
infinispan-4.0.0(repl-sync-jbmar) - infinispan + jbmar 1.1.2
infinispan-4.0.0(repl-sync-jbmar)-rXYZ - infinispan + jbmar with revision
Not sure what's the conclusion here tbh. The results of 1.1.2 almost
look opposite in each test.
I've also attached some information from previously run profiling
sessions with a couple of local machines we have in Neuchatel. I
profiled the faster of the two machines.
Actually, looking at this profiled data, these tests are for synchronous
replicated caches but I see no traces of actually reading the stream,
only writing to it, hmmmm.
I'm adding Externalizers to class table and implementing
marshaller/unmarshaller pooling as my next tasks.
Regards,
David M. Lloyd wrote:
> OK, I tried out a few things. You might want to try introducing these
> one at a time (i.e. update up to rev 173, then 174, then 175 and see
> how each one does). In particular, I think 175 has just as much
> chance of slowing things down as speeding them up - either you're
> getting tons of collisions in the hash table or the profiler is
> skewing the results there (maybe try filtering out
> org.jboss.marshalling.util.IdentityIntMap and java.lang.System to see
> if that gives a different picture).
>
> I feel pretty good about 173 and 174 though I think the profiler will
> skew 173 unless you have that UTFUtils filter installed. If 175 slows
> things down (outside of the profiler), let me know and I'll revert
> it. None of my tests showed much difference but I don't have any good
> benchmarks that really exercise that code right now.
>
> There's a couple things left to try yet, like looking at replacing
> ConcurrentReferenceHashMap (assuming that isn't the profiler again).
>
> ------------------------------------------------------------------------
> r175 | david.lloyd(a)jboss.com | 2009-05-08 00:17:46 -0500 (Fri, 08 May
> 2009) | 1 line
>
> Try a trick to decrease the liklihood of collisions
> ------------------------------------------------------------------------
> r174 | david.lloyd(a)jboss.com | 2009-05-08 00:04:39 -0500 (Fri, 08 May
> 2009) | 1 line
>
> Replacement caching is not economical; the cost is one extra hash
> table get for non-replaced objects, two hash table gets (total) for
> replaced objects. Removing the cache gets rid of the cost for
> non-replaced objects, while replaced objects now have to be replaced
> again before the single hash table hit.
> ------------------------------------------------------------------------
> r173 | david.lloyd(a)jboss.com | 2009-05-07 23:44:52 -0500 (Thu, 07 May
> 2009) | 1 line
>
> JBMAR-52 - Avoid extra copy of char array (1.5 of 2)
> ------------------------------------------------------------------------
>
> - DML
--
Galder Zamarreño
Sr. Software Maintenance Engineer
JBoss, a division of Red Hat