Thanks for the answer NIOFSDirectory is like an example. Degradation is also on MMapDirectory and SimpleFSDirectory
We are using elasticseach and it has: simplefs (SimpleFsDirectory), niofs (NIOFSDirectory), mmapfs (MMapDirectory) and hybridfs (NIOFSDirectory + MMapDirectory). And for us, while niofs was a little faster than other stores Yes FSDirectory works fast(both commits), but now it is difficult to test on prod elasticseach. But why is FSDirectory fast? How to understand this? чт, 8 апр. 2021 г. в 13:49, Adrien Grand <jpou...@gmail.com>: > > Hello, > > Why are you forcing NIOFSDirectory instead of using Lucene's defaults via > FSDirectory#open? I wonder if this might contribute to the slowdown you are > seeing given that access to the terms index tends to be a bit random. > > It's very unlikely we'll add back a toggle for this as there is no point in > holding the terms index in JVM heap when it could live in the OS cache > instead. > > On Thu, Apr 8, 2021 at 7:57 AM Никита Михайлов <mihaylovniki...@gmail.com> > wrote: > > > Hi. I noticed that after the upgrade from Lucene8.5.x to Lucene >=8.6, > > search became slower(example TopScoreDocCollector became 20-30% slower, > > from ElasticSearch - 50%). > > > > While testing, I realized that it happened after LUCENE-9257(commit > > e7a61ea). Bug or feature? Can add settings for isOffHeep? To make the > > developer explicitly make this choice > > > > Added a file that shows a simple demo that the search is slow > > Need to run on commit e7a61ea and 90aced5, you will notice how the speed > > drops to 30% > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > > For additional commands, e-mail: java-user-h...@lucene.apache.org > > > > -- > Adrien --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org