Will `index.store.preload` load files that aren't in `index.store.hybrid.mmap.extensions`?

In OpenSearch 2.6 (and above), there are two settings configuring mmap behaviour: index.store.preload and index.store.hybrid.mmap.extensions. What is the behaviour when index.store.preload is a superset of index.store.hybrid.mmap.extensions? Are only the filetypes in index.store.hybrid.mmap.extensions preloaded or are all files covered by index.store.preload preloaded?

Hey @borrowmayo ,

They way it works is that in case of hybrid directory, it will only delegate to underlying MMapDirectory based on index.store.hybrid.mmap.extensions (which in turn, has preload configured based on index.store.preload). So if index.store.preload is a superset (to clarify the case - it has all of index.store.hybrid.mmap.extensions + some more), the other extensions won’t be used for hybrid directory.

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