On Thu, 2015-08-27 at 11:23 +0300, Esther Goldbraich wrote: > We are using GC tuning options: Xgcpolicy:gencon , verbose:gc. > RAM: 64GB > Solr heap: -Xms512m -Xmx32768m > Index per server: 500G
Expecting "Your RAM size should be equal to index size"-posts to arrive in 3, 2, 1... > Surprisingly, running different setup on same machines, 64 collections / 1 > shard per collection gives significantly better results. > Any ideas? Compared to what? If your other scenario is to have 1 collection split over 64 shards, then the difference boils down to distributed search vs. single-shard search. There is a non-trivial overhead with doing distributed search, so if a collection fits well into a single shard (replicas does not count as distribution here), that is preferable. Come to think about it, distribution in itself might account for the difference between 4 & 5 that you are observing. Are you doing faceting as part of your test? - Toke Eskildsen, State and University Library, Denmark
