mirror of
https://github.com/postgres/postgres.git
synced 2025-05-02 11:44:50 +03:00
cea17ba07a
If both timeout indicators are set when we arrive at ProcessInterrupts, we've historically just reported "lock timeout". However, some buildfarm members have been observed to fail isolationtester's timeouts test by reporting "lock timeout" when the statement timeout was expected to fire first. The cause seems to be that the process is allowed to sleep longer than expected (probably due to heavy machine load) so that the lock timeout happens before we reach the point of reporting the error, and then this arbitrary tiebreak rule does the wrong thing. We can improve matters by comparing the scheduled timeout times to decide which error to report. I had originally proposed greatly reducing the 1-second window between the two timeouts in the test cases. On reflection that is a bad idea, at least for the case where the lock timeout is expected to fire first, because that would assume that it takes negligible time to get from statement start to the beginning of the lock wait. Thus, this patch doesn't completely remove the risk of test failures on slow machines. Empirically, however, the case this handles is the one we are seeing in the buildfarm. The explanation may be that the other case requires the scheduler to take the CPU away from a busy process, whereas the case fixed here only requires the scheduler to not give the CPU back right away to a process that has been woken from a multi-second sleep (and, perhaps, has been swapped out meanwhile). Back-patch to 9.3 where the isolationtester timeouts test was added. Discussion: <8693.1464314819@sss.pgh.pa.us>
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/.