David Turner 87e8367ece Fix testCreateAndRestoreSearchableSnapshot (#55147)
Fixes a couple of related failures in SearchableSnapshotsIntegTests.

Firstly, we were not correctly accounting for the case where the cache was so
small that some/all files were read directly; fixed this by only asserting that
the cache is definitely used if the corresponding node has a cache that's large
enough to hold the whole index.

Secondly, we were not permitting shards to be completely empty, which might be
the case (rarely) if there were not many documents indexed and the distribution
of IDs was a bit unlucky; fixed this by asserting that we get stats for at
least one file for the whole index, rather than for each shard separately.

Closes #55126
2020-04-14 11:54:46 +01:00
..