mikemccand commented on pull request #177: URL: https://github.com/apache/lucene/pull/177#issuecomment-866067673
> I have no idea why the facetting stuff at the beginning of the bench output is so badly behaving with MMapDirectory#v2 on top of project panama, I'll ignore this for now. Maybe @mikemccand has an idea! The rest looks perfectly fine to me from the performance (19 runs). Yeah that is strange. The impact is sizable. These tasks effectively run a `MatchAllDocsQuery`, and for each hit (doc) decodes the packed delta-coded int ordinals from a `BinaryDocValues` field, incrementing counters in a big `int[]`. To the `MMapDirectory` it should look like it's doing a big sequential scan of that `BinaryDocValues` field for each segment. Surely this should be easy for `mmap` ;) Maybe we should run profiler ... maybe something silly is happening, like we are randomly seeking on every hit unnecessarily ... -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org
