: However, when sort by "ptime desc", the result is consistent. : The dateDeboost generate the time-weight from ptime, which is multiplied by : the score.
As Erick mentioned, you haven't given us enough details to make any educated guesses as to what problem you are seeing. My wild, uneducated, shot in the dark guess: are you populating "ptime" using a default of "NOW"? If so, can you rule out the function as an issue by asking for fl=id,ptime and confirming that the ptime for these documents sometimes varies slightly? "NOTE: Allthough it is possible to configure a TrieDateField instance with a default value of "NOW" to compute a timestamp of when the document was indexed, this is not advisable when using SolrCloud since each replica of the document may compute a slightly different value. TimestampUpdateProcessorFactory is recomended instead." https://lucene.apache.org/solr/4_6_0/solr-core/org/apache/solr/schema/TrieDateField.html https://lucene.apache.org/solr/4_6_0/solr-core/org/apache/solr/update/processor/TimestampUpdateProcessorFactory.html -Hoss
