此次更新的版本包括：9.0.2, 8.4.6, 8.3.13, 8.2.19, 8.1.23.

另外这也是最后一次 8.1 版本的更新，8.1 版本已经不再被支持，建议用户立即升级，详情请看发布支持策略。

详细的改进记录如下（174个bug修复）：

• Avoid failure when trying to report an impending transaction wraparound condition from outside a transaction. This oversight prevented recovery after transaction wraparound got too close, because database startup processing would fail, backpatched to all versions.
• Fix recovery from base backup when the starting checkpoint WAL record is not in the same WAL segment as its redo point, backpatched to all supported versions.
• Force default wal_sync_method to be fdatasync for Linux, backpatched to all supported versions.
• Fix memory leak with ANALYZE and complex index expressions, backpatched to all supported versions.
• Fix memory leak in contrib/xml2 functions, backpatched to all supported versions.
• Fix for segfault in pgcrypto when attempting to access an undefined public key, backpatched to all supported versions.
• Prevent inlining an SQL function with multiple OUT parameters, backpatched to all supported versions.
• Fix bugs in WAL replay logic for GIN indexes, backpatched to 8.2.
• Fix segfault when accept() or a call made right after accepting a connection fails when server is compiled with GSSAPI support, backpatched to 8.3.
• Fix error handling in tempfile deletion with log_temp_files active, backpatched to 8.3.
• Prevent slowing of of autovacuum workers because of leakage in cost parameter over life of worker, backpatched to 8.3.
• Check for too many children before returning "okay to proceed", backpatched to 8.4.
• Improve performance of internal tuplestore structures for window functions, backpatched to 8.4.

9.0.2 ：

• Fix low-risk potential denial of service against RADIUS login.
• Make OFF keyword unreserved.
• Fix bug in tracking of latest removed WAL segment in streaming replication.
• Fix for buffer overrun in pg_upgrade.
• Fix memory leak in autovacuum launcher.
• Fix for race condition in transaction ID assignment and lock acquisition in hot standby.
• Improve performance for parallel restore with many blobs.