Thanks folks. It looks like the sweet spot where I get comparable results is at 30 concurrent threads. It progressively degrades from there as I increases the number of concurrent threads in the test script.
This made me think that something is configured in Tomcat ((Solr4) that is not comparatively set in Solr 6. The only thing I found that would make sense is the connector max number threads that we have set at 800 for Tomcat. However, it jetty.xml, maxThreads is set to 50000. Not sure if these two maxThreads have the same effect. I thought about Yonik suggestion a little bit. Where I am scratching my head is that if specific kind of queries where more expensive than others, should this be reflected even at 30 concurrent threads? Anyway, still digging. On Wed, Nov 23, 2016 at 9:56 AM, Walter Underwood <wun...@wunderwood.org> wrote: > I recently ran benchmarks on 4.10.4 and 6.2.1 and found very little > difference in query performance. > > This was with 8 million documents (homework problems) from production. I > used query logs from > production. The load is a constant number of requests per minute from 100 > threads. CPU usage > is under 50% in order to avoid congestion. The benchmarks ran for 100 > minutes. > > Measuring median and 95th percentile, the times were within 10%. I think > that is within the > repeatability of the benchmark. A different number of GCs could make that > difference. > > wunder > Walter Underwood > wun...@wunderwood.org > http://observer.wunderwood.org/ (my blog) > > > > On Nov 23, 2016, at 8:14 AM, Bram Van Dam <bram.van...@intix.eu> wrote: > > > > On 22/11/16 15:34, Prateek Jain J wrote: > >> I am not sure but I heard this in one of discussions, that you cant > migrate directly from solr 4 to solr 6. It has to be incremental like solr > 4 to solr 5 and then to solr 6. I might be wrong but is worth trying. > > > > Ideally the index needs to be upgraded using the IndexUpgrader. > > > > Something like this should do the trick: > > > > java -cp lucene-core-6.0.0.jar:lucene-backward-codecs-6.0.0.jar > > org.apache.lucene.index.IndexUpgrader /path/to/index > > > > - Bram > >
