I'm not sure about _performance_, but I'm pretty sure you don't want to be faceting on docValued SortableTextField (and faceting on non-docValued SortableTextField, though I think technically possible, works against uninverted _indexed_values, so ends up doing something entirely different): https://issues.apache.org/jira/browse/SOLR-13056.
TL;DR: with SortableTextField bulk faceting happens over docValues (which for SortableTextField contains the full sort value string) and refinement happens against indexed values (which are tokenized). So it can behave very strangely, at least in multi-shard collections. See also: https://issues.apache.org/jira/browse/SOLR-8362 Quick clarification, you say "non Docvalued String Field" ... I'm assuming you're talking about "StrField", not "TextField". wrt performance difference, I'm willing to bet (though not certain) that you're really simply noticing a discrepancy between docValues and non-docValues faceting -- accordingly, for your use case I'd expect faceting against StrField _with_ docValues to have similar performance to SortableTextField with docValues. Further possibly-relevant discussion can be found in the following thread: http://mail-archives.apache.org/mod_mbox/lucene-solr-user/202006.mbox/%3CCAF%3DheHFd6GBABzKzDQPTfpYUUQJXxYwue4OC86QOm_AR0X3_ZQ%40mail.gmail.com%3E On Thu, Jan 28, 2021 at 7:25 PM Jae Joo <jaejo...@gmail.com> wrote: > I am wondering that the performance of facet of DocValued SortableText > Field is slower than non Docvalued String Field. > > Does anyone know why? > > > Thanks, > > Jae >
