990fe3c4ed
When a standby server follows the master using WAL archive, and it chooses a new timeline (recovery_target_timeline='latest'), it only fetches the timeline history file for the chosen target timeline, not any other history files that might be missing from pg_xlog. For example, if the current timeline is 2, and we choose 4 as the new recovery target timeline, the history file for timeline 3 is not fetched, even if it's part of this server's history. That's enough for the standby itself - the history file for timeline 4 includes timeline 3 as well - but if a cascading standby server wants to recover to timeline 3, it needs the history file. To fix, when a new recovery target timeline is chosen, try to copy any missing history files from the archive to pg_xlog between the old and new target timeline. A second similar issue was with the WAL files. When a standby recovers from archive, and it reaches a segment that contains a switch to a new timeline, recovery fetches only the WAL file labelled with the new timeline's ID. The file from the new timeline contains a copy of the WAL from the old timeline up to the point where the switch happened, and recovery recovers it from the new file. But in streaming replication, walsender only tries to read it from the old timeline's file. To fix, change walsender to read it from the new file, so that it behaves the same as recovery in that sense, and doesn't try to open the possibly nonexistent file with the old timeline's ID. |
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| contrib | ||
| doc | ||
| src | ||
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| COPYRIGHT | ||
| GNUmakefile.in | ||
| Makefile | ||
| README | ||
| README.git | ||
| aclocal.m4 | ||
| configure | ||
| configure.in | ||
README
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. Changes between all PostgreSQL releases are recorded in the file HISTORY. 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/.