: Lucene is detecting our SSDs as Spinning disks, as seen through the admin metrics endpoint: : : : * CONTAINER.fs.coreRoot.spins: true : * CONTAINER.fs.spins: true
the spins metric is always going to return whatever the Lucene IOUtils think the disk is -- there is no setting you can use to override that and make the metric "lie" (from it's perspective) about what lucnee thinks *BUT* ... what lucene thinks only matters in terms of the *DEFAULT* behavior when configuring ConcurrentMergeScheduler... : However we can see in the `system.properties` endpoint we are overriding it: : : : * lucene.cms.override_spins: "false" ...with that property set, and use ConcurrentMergeScheduler, then it's default behavior will be to pick "MaxMergesAndThreads" based on hueristics accordingly. If you don't use ConcurrentMergeScheduler, or have explicitly configured the MaxMergesAndThreads, then that system property won't matter. (but either way, the *.spins metrics are going to tell you what lucene things the disk is) FWIW: Instead of focusing on setting lucene.cms.override_spins to override the spins/ssd hueristics, you may want to just focus on explicitly setting the max merges and threads explicitly since that gives you more direct control ... in 9.x the spins hueristic will go away entirely and the same defaults are used entirely regardless. -Hoss http://www.lucidworks.com/
