Summary:
Right now, if underlying read returns fewer bytes than asked for, RandomAccessFileReader::MultiRead() still returns those in the buffer to upper layer. This can be a surprise to upper layer.
This is unlikely to cause incorrect data. To cause incorrect data, checksum checking in upper layer should pass with short reads, whose chance is low.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8941
Test Plan: Run stress tests for a while
Reviewed By: anand1976
Differential Revision: D31085780
fbshipit-source-id: 999adf2d6c2712f1323d14bb68b678df59969973
fcce1f2c7a