[PROTON-30] The driver cannot be cleanly used in a multi-threaded application due to pn_driver_wait

• Type: Wish
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: proton-0.16.0
• Component/s: proton-c
• Assignee: Alan Conway
• Reporter: Ted Ross
• Created: 18/Sep/12 21:53
• Updated: 13/Dec/16 18:53
• Resolved: 15/Nov/16 17:07

Description

An efficient multi-threaded application based on proton-c will want to have one thread blocked on pn_driver_wait if there's no other work for it to do. Unfortunately, pn_driver_wait does thread-unsafe things with internal driver data structures before and after it blocks on the FD set.

The alternatives are to quiesce all threads prior to calling pn_driver_wait (which is undesirable for performance reasons) or to divide pn_driver_wait into three sections, the first and third of which can be invoked with a lock held and the second of which (the poll call) can be invoked without a lock.

Alternatively, a driver API better suited to multi-threading could be developed.

Issue Links

• duplicates: PROTON-1344 Provide C "proactor" API for multi-threaded proton applications