a39e78b710
DetermineSleepTime() was previously called without blocked signals. That's not good, because it allows signal handlers to interrupt its workings. DetermineSleepTime() was added in 9.3 with the addition of background workers (da07a1e856511), where it only read from BackgroundWorkerList. Since 9.4, where dynamic background workers were added (7f7485a0cde), the list is also manipulated in DetermineSleepTime(). That's bad because the list now can be persistently corrupted if modified by both a signal handler and DetermineSleepTime(). This was discovered during the investigation of hangs on buildfarm member anole. It's unclear whether this bug is the source of these hangs or not, but it's worth fixing either way. I have confirmed that it can cause crashes. It luckily looks like this only can cause problems when bgworkers are actively used. Discussion: 20140929193733.GB14400@awork2.anarazel.de Backpatch to 9.3 where background workers were introduced.
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. PostgreSQL has many language interfaces, many of which are listed here: http://www.postgresql.org/download See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.