Hi all,
We observe that solr query time increases significantly with the number of rows requested, even all we retrieve for each document is just fl=id,score. Debugged a bit and see that most of the increased time was spent in BinaryResponseWriter, converting lucene document into SolrDocument. Inside convertLuceneDocToSolrDoc(): https://github.com/apache/lucene-solr/blob/df874432b9a17b547acb24a01d3491 839e6a6b69/solr/core/src/java/org/apache/solr/response/ DocsStreamer.java#L182 for (IndexableField f : doc.getFields()) I am a bit puzzled why we need to iterate through all the fields in the document. Why can’t we just iterate through the requested fields in fl? Specifically: https://github.com/apache/lucene-solr/blob/df874432b9a17b547acb24a01d3491 839e6a6b69/solr/core/src/java/org/apache/solr/response/ DocsStreamer.java#L156 if we change sdoc = convertLuceneDocToSolrDoc(doc, rctx.getSearcher().getSchema()) to sdoc = convertLuceneDocToSolrDoc(doc, rctx.getSearcher().getSchema(), fnames) and just iterate through fnames in convertLuceneDocToSolrDoc(), there is a significant performance boost in our case, the query time increase from rows=128 vs rows=500 is much smaller. Am I missing something here? Thanks, Wei
