Release Notes: Since 220.127.116.11, problems were fixed with hot-restart where the old process would not always stop, cookie capture was fixed (as it was broken since the frontend/backend split), critical startup errors are now reported on the console, and a failing server will no longer consume pending requests from the global queue. This last problem was the cause of many 503 errors for some people.
Release Notes: The connections regulation mechanism could send more connections than the allowed limit to a server when this server had just rejected a connection attempt; for servers with very low connection limits such as mongrel, this could easily trigger timeouts. The slowstart mechanism could return a limit of zero connections for very low maxconn values, causing servers to re-enter the farm a bit late.
Release Notes: Several timeouts were not correctly updated on some rare occasions. A possible segfault when using "url_param check_post" has been fixed. regparm is disabled on gcc versions < 3. "use_backend" would not correctly consider "unless". This last change should probably be the real reason to upgrade, as check_post is rarely used.
Release Notes: The queue/dequeue logic was reworked; using a low server maxconn value to serialize requests could result in some requests never being served. Users are encouraged to upgrade, especially those running haproxy in front of mongrel. All versions are affected. Version 18.104.22.168 was also released to address this problem in the previous branch.
Release Notes: Building with gcc 4.3 has been fixed. A condition where statistics could be truncated if exactly zero bytes remained in the buffer has been fixed. An event starvation that caused connection acceptance to slow down when approaching 40000 concurrent connections at gigabit speed has been fixed.
Release Notes: This release fixes building of rbtree on BSD, and fixes an early server close after a client close. These are long-standing fixes that were available but not in any released version.
Release Notes: Many new features, including stats updates (HTTP, UNIX, and SNMP), enhancements to server checks such as tracking and dynamic intervals, the addition of the leastconn load-balancing algorithm and POST parameter analysis, a fully transparent mode on Linux, better handling of connection failures (dead server avoidance and turn-around state), support for inter-site off-loading through redirects, updates to the build process, and large documentation updates.
Release Notes: Several minor bugfixes and documentation updates have been merged. Nothing critical was done, but since it also means greater reliability, it's probably the right moment for distribution packagers to upgrade.
Release Notes: Several minor bugs have been fixed. A major bug that might have caused object truncation under Linux 2.6 with sepoll and slow servers has been fixed. It is now possible to prepend the "no" keyword in front of options. The GNU Makefile has been rewritten to become more distribution packager friendly. The configuration manual has received a large update, and is almost complete with 158 pages of detailed keywords and options.
Release Notes: A lot of new features were added, starting with dynamic weight support, logging via a unix socket, many improvements to stats, an http_proxy mode, graceful server shutdown, more convenient timeout handling, server farm state propagation to outer components, more config checks and hints, and a port to AIX 5.3. Several bugs were fixed, and a lot of cleanups and small optimizations were made.