`resultId` sounds like it might be a relatively high-cardinality field (lots of unique values)? What's your number of shards, and replicas per shard? SOLR-15008 (note: not a bug) describes a situation that may be fundamentally similar to yours (though to be sure it's impossible to say for sure without more information): https://issues.apache.org/jira/browse/SOLR-15008?focusedCommentId=17236213#comment-17236213
In particular, the explanation and troubleshooting advice on the linked comment might be relevant? "dvhash" is _not_ mentioned on that SOLR-15008, but if the `processId` main query significantly reduces the domain -- or more specifically, if `resultId` is high-cardinality overall, but the cardinality of `resultId` values _associated with a particular query_ is low -- you might consider trying `"method"="dvhash"` (which should bypass OrdinalMap creation and array allocation, if either/both of those contribute to the latency you're finding). Michael On Fri, Feb 5, 2021 at 4:42 PM mmb1234 <m...@vmware.com> wrote: > Hello, > > I am seeing very slow response from json faceting against a single core > (though core is shard leader in a collection). > > Fields processId and resultId are non-multivalued, indexed and docvalues > string (not text). > > Soft Commit = 5sec (opensearcher=true) and Hard Commit = 10sec because new > docs are constantly being indexed with 95% new and 5% overwritten > (overwrite=true; no atomic update). Caches are not considered useful due to > commit frequency. > > Solr is v8.7.0 on openjdk11. > > Is there any way to improve json facet QTime? > > ## query only > curl > ' > http://localhost:8983/solr/TestCollection_shard1_replica_t3/query?q=processId:xxxx-xxx-xxx-xxx-xxxxx&rows=0 > ' > -d ' > { > "responseHeader":{ > "zkConnected":true, > "status":0, > "QTime":552, > "params":{ > "q":"processId:xxxx-xxx-xxx-xxx-xxxxx", > "cache":"false", > "rows":"0"}}, > "response":{"numFound":231311,"start":0,"numFoundExact":true,"docs":[] > }} > > ## json facet takes 46secs > curl > ' > http://localhost:8983/solr/TestCollection_shard1_replica_t3/query?q=processId:xxxx-xxx-xxx-xxx-xxxxx&rows=0 > ' > -d ' > json.facet={ > categories:{ > "type": "terms", > "field" : "resultId", > "limit" : 1 > } > }' > { > "responseHeader":{ > "zkConnected":true, > "status":0, > "QTime":46972, > "params":{ > "q":"processId:xxxx-xxx-xxx-xxx-xxxxx", > "json.facet":"{ categories:{ \"type\": \"terms\", > \"field\" : \"resultId\", \"limit\" : 1 }}", > "rows":"0"}}, > "response":{"numFound":231311,"start":0,"numFoundExact":true,"docs":[] > }, > "facets":{ > "count":231311, > "categories":{ > "buckets":[{ > "val":"xxxxxxxxx", > "count":943}]}}} > > > ## visualvm CPU sampling almost all time spent in lucene: > > org.apache.lucene.util.PriorityQueue.downHeap() 23,009 ms > > org.apache.lucene.codecs.lucene80.Lucene80DocValuesProducer$TermsDict.next() > 13,268 ms > > > > -- > Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html >
