2346df6fc3
We don't determine the position at which a process waiting for a lock should insert itself into the wait queue until we reach ProcSleep(), and we may at that point discover that we must insert ourselves ahead of everyone who wants a conflicting lock, in which case we obtain the lock immediately. Up until now, a no-wait lock acquisition would fail in such cases, erroneously claiming that the lock couldn't be obtained immediately. Fix that by trying ProcSleep even in the no-wait case. No back-patch for now, because I'm treating this as an improvement to the existing no-wait feature. It could instead be argued that it's a bug fix, on the theory that there should never be any case whatsoever where no-wait fails to obtain a lock that would have been obtained immediately without no-wait, but I'm reluctant to interpret the semantics of no-wait that strictly. Robert Haas and Jingxian Li Discussion: http://postgr.es/m/CA+TgmobCH-kMXGVpb0BB-iNMdtcNkTvcZ4JBxDJows3kYM+GDg@mail.gmail.com
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at:
https://www.postgresql.org/docs/devel/
In particular, information about building PostgreSQL from the source
code can be found at:
https://www.postgresql.org/docs/devel/installation.html
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.