Am 06.08.2015 um 14:33 schrieb Upayavira: > Typically such performance issues with faceting are to do with the time > spend uninverting the index before calculating the facet counts. > > If you indexed the fields with docValues enabled, perhaps you could then > use them for faceting, which might improve performance.
Well, this is against my observations. When I used uninverted fields without docValues I had a much better 99 percentile qtime but a very high heap consumption. Now with docValues the heap usage went down, but the 99 percentile qtime for MatchAllDocsQuery(*:*) went up to above 33 seconds. > > If you are using a non-docValues field, and the second query is faster, > then you could add the query to your static warming, look for > newSearcher in your solrconfig.xml. That will execute your query, > warming the caches used by faceting, before a new searcher is made > available for searches. The q=*.* with sorting and facetting is always the first query I'm doing at static warming and it helped until switching to docValues :-( Bernd > > Upayavira > > On Thu, Aug 6, 2015, at 12:38 PM, Toke Eskildsen wrote: >> On Thu, 2015-08-06 at 13:00 +0200, Bernd Fehling wrote: >>> Single Index Solr 4.10.4, optimized Index, 76M docs, 235GB index size. >>> >>> I was analysing my solr logs and it turned out that I have some queries >>> which are above 30 seconds qtime while normally the qtime is below 1 second. >>> Looking closer about the queries it turned out that this is for >>> MatchAllDocsQuery(*:*). >>> Next was to turn debugQuery on and see where the bottleneck is. >>> The result was that the facetting is consuming most of the qtime. >>> >>> So the question is, are facets or is facetting not cached? >> >> As far as I know it is not. 35 seconds for a match-all faceting sounds >> fairly on par with what we are seeing (250M docs, 900GB shard). >> >> Of course response time is very depending on the field itself. If you >> have very few unique values in your facet field(s), you might try >> facet.method=enum. If that is not the case, your best bet would probably >> be to cache the match-all outside of Solr. >> >>> My assumption is that the queryResultCache is catching such a >>> MatchAllDocsQuery(*:*). >> >> It only stores the docIDs. >> >> I don't know why there is is no all_parameters -> complete_response >> cache in Solr. >> >> - Toke Eskildsen, State and University Library, Denmark >> >>
