Before anyone asks, these results were obtained warm. On 20 Sep 2012, at 14:39, Tom Mortimer <tom.m.f...@gmail.com> wrote:
> Hi all, > > After reading > http://carsabi.com/car-news/2012/03/23/optimizing-solr-7x-your-search-speed/ > , I thought I'd do my own experiments. I used 2M docs from wikipedia, indexed > in Solr 4.0 Beta on a standard EC2 large instance. I compared an unsharded > and 2-shard configuration (the latter set up with SolrCloud following the > http://wiki.apache.org/solr/SolrCloud example). I wrote a simple python > script to randomly throw queries from a hand-compiled list at Solr. The only > "extra" I had turned on was facets (on document category). > > To my surprise, the performance of the 2-shard configuration is almost > exactly half that of the unsharded index - > > unsharded > 4983912891 results in 24920 searches; 0 errors > 70.02 mean qps > 0.35s mean query time, 2.25s max, 0.00s min > 90% of qtimes <= 0.83s > 99% of qtimes <= 1.42s > 99.9% of qtimes <= 1.68s > > 2-shard > 4990351660 results in 24501 searches; 0 errors > 34.07 mean qps > 0.66s mean query time, 694.20s max, 0.01s min > 90% of qtimes <= 1.19s > 99% of qtimes <= 2.12s > 99.9% of qtimes <= 2.95s > > All caches were set to 4096 items, and performance looks ok in both cases > (hit ratios close to 1.0, 0 evictions). I gave the single VM -Xmx1G and each > shard VM -Xmx500M. > > I must be doing something stupid - surely this result is unexpected? Does > anybody have any thoughts where it might be going wrong? > > cheers, > Tom >
