File Locking Control in HDF5 1.10.x

Version 1.10 of the HDF5 library uses a file locking scheme to help prevent reader/writer access patterns that can cause library errors, particularly with respect to the singlewriter/multiple-readers (SWMR) access pattern. Although this scheme works well for many users, it has come to our attention that it can cause problems for others. Additional control over the file locking scheme would mitigate the issues that have been described to us.

This RFC provides an overview of the locking scheme, describes the problems that users have been encountering, and proposes some solutions. The implementation of the solutions are targeted for HDF5 1.10.1 (target release date: December 2016).