Redis 2.6 release notes
+=======================
-Migrating from 2.4 to 2.6
-=========================
+** IMPORTANT ** Check the 'Migrating from 2.4 to 2.6' section at the end of
+ this file for information about what changed between 2.4 and
+ 2.6 and how this may affect your application.
-Redis 2.4 is mostly a strict subset of 2.6. However there are a few things
-that you should be aware of:
+--------------------------------------------------------------------------------
+Upgrade urgency levels:
-* You can't use .rdb and AOF files generated with 2.6 into a 2.4 instance.
-* 2.4 slaves can be attached to 2.6 masters, but not the contrary, and only
- for the time needed to perform the version upgrade.
+LOW: No need to upgrade unless there are new features you want to use.
+MODERATE: Program an upgrade of the server, but it's not urgent.
+HIGH: There is a critical bug that may affect a subset of users. Upgrade!
+CRITICAL: There is a critical bug affecting MOST USERS. Upgrade ASAP.
+--------------------------------------------------------------------------------
-There are also a few API differences, that are unlikely to cause problems,
-but it is better to keep them in mind:
+--[ Redis 2.6.7 ]
-* SORT now will refuse to sort in numerical mode elements that can't be parsed
- as numbers.
-* EXPIREs now all have millisecond resolution (but this is very unlikely to
- break code that was not conceived exploting the previous resolution error
- in some way.)
-* INFO output is a bit different now, and contains empty lines and comments
- starting with '#'. All the major clients should be already fixed to work
- with the new INFO format.
+UPGRADE URGENCY: MODERATE (unless you BLPOP using the same key multiple times).
----------
-CHANGELOG
----------
+* [BUGFIX] Don't crash if BLPOP & co are called with the same key repeated
+ multiple times (Issue #801).
-What's new in Redis 2.6.0
-=========================
+--[ Redis 2.6.6 ]
+
+UPGRADE URGENCY: CRITICAL if you experienced one more more crashes.
+ MODERATE if Redis is running fine for you.
+
+* [BUGFIX] Jemalloc updated to 3.2.0.
+
+--[ Redis 2.6.5 ]
+
+UPGRADE URGENCY: MODERATE
+
+Warning: this release of Redis introduces a different behavior in MULTI/EXEC
+ handling of errors. This was done because the new behavior is safer
+ compared to the old one, and should not break any code targeting
+ Redis 2.6 in a critical way.
+
+ For more information check http://redis.io/topics/transactions
+
+* [IMPROVED] RDB/AOF childern now log amount of additional memory used
+ because of copy on write.
+* [BUGFIX] MIGRATE non critical fixes (see commits for details).
+* [BUGFIX] MULTI/EXEC: now EXEC aborts on errors before EXEC.
+* [BUGFIX] Fix integer overflow in zunionInterGenericCommand resulting
+ into Z[INTER|UNION][STORE] commands to crash under extremely
+ unlikely conditions (almost impossible in real world).
+* [BUGFIX] EVALSHA is now case insensitive (and will not crash).
+
+--[ Redis 2.6.4 ]
+
+UPGRADE URGENCY: LOW
+
+* [IMPROVED] BSD license and copyright notice added to every .c and .h file.
+
+--[ Redis 2.6.2 ]
+
+UPGRADE URGENCY: LOW
+
+* [BUGFIX] The compilation fix for RHLE5 in 2.6.1 was broken. Fixed.
+* [IMPROVED] Linenoise updated, now supports Ctrl+w.
+
+---[ Redis 2.6.1 ]
+
+UPGRADE URGENCY: LOW
+
+* [BUGFIX] Compilation on Linux < 2.6.17 or glibc < 2.6 fixed (RHLE5 & co).
+
+---[ Redis 2.6.0 ]
+
+UPGRADE URGENCY: HIGH
+
+* [BUGFIX] Allow AUTH when server is in -BUSY state because of a slow script.
+* [BUGFIX] MULTI/EXEC flow now makes sense when observed in MONITOR
+* [BUGFIX] SCRIPT KILL now uses different error prefixes for different errors.
+* [BUGFIX] Default memory limit for 32bit archs lowered from 3.5 to 3 GB.
+* [BUGFIX] redis-check-dump is now compatible with RDB files generated by 2.6.
+* [IMPROVED] New field in INFO: slave_read_only.
+
+---[ Redis 2.5.14 (2.6 Release Candidate 8) ]
+
+* [BUGFIX] Fixed compilation on FreeBSD.
+* [IMPROVED] SRANDMEMBER <count> that returns multiple random elements.
+* [IMPROVED] Sentinel backported to 2.6. It will be taken in sync with 2.8.
+* [IMPROVED] Helper function for scripting to return errors and status replies.
+* [IMPROVED] SORT by nosort [ASC|DESC] uses sorted set elements ordering.
+* [BUGFIX] Better resistence to system clock skew.
+* [IMPROVED] Warn the user when the configured maxmemory seems odd.
+* [BUGFIX] Hashing function is now murmurhash2 for security purposes.
+* [IMPROVED] Install script no longer uses a template but redis.conf itself.
+
+---[ Redis 2.5.13 (2.6 Release Candidate 7) ]
+
+UPGRADE URGENCY: HIGH
+
+* [BUGFIX] Theoretical bug in ziplist fixed.
+* [BUGFIX] Better out of memory handling (Log produced in log file).
+* [BUGFIX] Incrementally flush RDB file on slave side while performing the
+ first synchronization with the master. This makes Redis less
+ blocking in environments where disk I/O is slow.
+* [BUGFIX] Don't crash with Lua's redis.call() without arguments.
+* [BUGFIX] Don't crash after a big number of Lua calls on 32 bit systems
+ because of a failed assertion.
+* [BUGFIX] Fix SORT behaviour when called from scripting.
+* [BUGFIX] Adjust slave PING period accordingly to REDIS_HZ define.
+* [BUGFIX] BITCOUNT: fix crash on overflowing arguments.
+* [BUGFIX] Return an error when SELECT argument is not an integer.
+* [BUGFIX] Blocking operations on lists were completely reimplemented for
+ correctness. Now blocking list ops and pushes originated from
+ Lua scripts will play well together and will be replicated
+ and transmitted to the AOF correctly.
+* [IMPROVED] Send async PING before starting replication to avoid blocking if
+ master allows us to connect but it is actually not able to reply.
+* [IMPROVED] Support slave-priority for Redis Sentinel.
+* [IMPROVED] Hiredis library updated.
+
+---[ Redis 2.5.12 (2.6 Release Candidate 6) ]
-UPGRADE URGENCY: We suggest new users to start with 2.6.0, and old users to
- upgrade after some testing of the application with the new
- Redis version.
+UPGRADE URGENCY: MODERATE.
+
+* [BUGFIX] Fixed a timing attack on AUTH (Issue #560).
+* [BUGFIX] Don't assume that "char" is signed.
+* [BUGFIX] Check that we have connection before enabling pipe mode.
+* [BUGFIX] Use the optimized version of the function to convert a double to
+ its string representation. Compilation was disabled because of
+ a typo in the #if statement.
+* [IMPROVED} REPLCONF internal command introduced, now INFO shows slaves with
+ correct port numbers. This makes 2.5.12 Redis Sentinel compatible.
+* [IMPROVED] Truncate short write from the AOF for a cleaner restart. On short
+ writes (for instance out of space) Redis will now try to remove
+ the half-written data so that the next restart will work without
+ the need for the "redis-check-aof" utility.
+* [IMPROVED] New in INFO: aof_last_bgrewrite_status
+* [IMPROVED] Allow Pub/Sub in contexts where other commands are blocked.
+* [BUGFIX] mark fd as writable when EPOLLERR or EPOLLHUP is returned by
+ epoll_wait.
+
+---[ Redis 2.5.11 (2.6 Release Candidate 5) ]
+
+UPGRADE URGENCY: HIGH.
+
+* [BUGFIX] Fixed Hash corruption when loading an RDB file generated by
+ previous versions of Redis that encoded hashes using
+ a different ziplist encoding format for small integers.
+ All the fileds that are integers in the range 0-255 may not
+ be recognized, or duplicated un updates, causing a crash
+ when the ziplist is converted to a real hash. (Issue #547).
+* [BUGFIX] Fixed the count of memory used by output buffers in the
+ setDeferredMultiBulkLength() function.
+
+---[ Redis 2.5.10 (2.6 Release Candidate 4) ]
+
+UPGRADE URGENCY: HIGH.
+
+* [BUGFIX] Allow PREFIX to be overwritten on "make install".
+* [BUGFIX] Run the test with just one client if the computer is slow.
+* [BUGFIX] Event port support in our event driven libray.
+* [BUGFIX] Jemalloc updated to 3.0.0. This fixes a possibly AOF rewrite issue.
+ See https://github.com/antirez/redis/issues/504 for info.
+* [BUGFIX] Fixed issue #516: ZINTERSTORE / ZUNIONSTORE with mixed sets/zsets.
+* [BUGFIX] Set fd to writable when poll(2) detects POLLERR or POLLHUP event.
+* [BUGFIX] Fixed RESTORE hash failure (Issue #532).
+* [IMPROVED] Allow an AOF rewrite buffer > 2GB (Related to issue #504).
+* [IMPROVED] Server cron function frequency is now configurable (REDIS_HZ).
+* [IMPROVED] Better, less blocking expired keys collection algorithm.
+* [FEATURE] New commands: BITOP and BITCOUNT.
+* [FEATURE] redis-cli --pipe for mass import.
+
+What's new in Redis 2.5.9 (aka 2.6 Release Candidate 3)
+=======================================================
+
+UPGRADE URGENCY: critical, upgrade ASAP.
+
+* [BUGFIX] Fix for issue #500 (https://github.com/antirez/redis/pull/500).
+ Redis 2.6-RC1 and RC2 may corrupt ziplist-encoded sorted sets
+ produced by Redis 2.4.x.
+* [BUGFIX] Fixed several bugs in init.d script.
+* [BUGFIX] syncio.c functions modified for speed and correctness. On osx
+ (and possibly other BSD-based systems) the slave would block on
+ replication to send the SYNC command when the master was not
+ available. This is fixed now, but was not affecting Linux installs.
+* Now when slave-serve-stale-data is set to yes and the master is down, instead
+ of reporting a generic error Redis replies with -MASTERDOWN.
+
+What's new in Redis 2.5.8 (aka 2.6 Release Candidate 2)
+=======================================================
+
+UPGRADE URGENCY: high for all the users of the KEYS command, otherwise low.
+
+* [BUGFIX] Fix for KEYS command: if the DB contains keys with expires the KEYS
+ command may return the wrong output, having duplicated or missing
+ keys. See issue #487 and #488 on github for details.
+
+What's new in Redis 2.5.7 (aka 2.6 Release Candidate 1)
+=======================================================
+
+UPGRADE URGENCY: upgrade not recommended because this is an RC release.
+
+* This is the first release candidate for Redis 2.6. We are not aware of
+ bugs, but part of this code is young and was never tested in production
+ environments, so handle with care.
+
+An overview of new features and changes in Redis 2.6.x
+======================================================
* Server side Lua scripting, see http://redis.io/commands/eval
* Virtual Memory removed (was deprecated in 2.4)
in slaves.
* Milliseconds resolution expires, also added new commands with milliseconds
precision (PEXPIRE, PTTL, ...).
-* Clinets max output buffer soft and hard limits. You can specifiy different
+* Better memory usage for "small" lists, ziplists and hashes when fields or
+ values contain small integers.
+* Read only slaves.
+* New bit opeations: BITCOUNT and BITOP commands.
+* Clients max output buffer soft and hard limits. You can specifiy different
limits for different classes of clients (normal,pubsub,slave).
+* More incremental (less blocking) expired keys collection algorithm, in
+ practical terms this means that Redis is more responsive when a very
+ big number of keys expire about at the same time.
* AOF is now able to rewrite aggregate data types using variadic commands,
often producing an AOF that is faster to save, load, and is smaller in size.
* Every redis.conf directive is now accepted as a command line option for the
redis-server binary, with the same name and number of arguments.
* Hash table seed randomization for protection against collisions attacks.
* Performances improved when writing large objects to Redis.
+* Integrated memory test, see redis-server --test-memory.
+* INCRBYFLOAT and HINCRBYFLOAT commands.
+* New DUMP, RESTORE, MIGRATE commands (back ported from Redis Cluster to 2.6).
+* CRC64 checksump in RDB files.
+* Better MONITOR output and behavior (now commands are logged before execution).
+* "Software Watchdog" feature to debug latency issues.
* Significant parts of the core refactored or rewritten. New internal APIs
and core changes allowed to develop Redis Cluster on top of the new code,
however for 2.6 all the cluster code was removed, and will be released with
* New statistics about how many time a command was called, and how much
execution time it used (INFO commandstats).
* More predictable SORT behavior in edge cases.
-* INCRBYFLOAT and HINCRBYFLOAT commands.
+* Better support for big endian and *BSD systems.
+* Build system improved.
+
+Migrating from 2.4 to 2.6
+=========================
+
+Redis 2.4 is mostly a strict subset of 2.6. However there are a few things
+that you should be aware of:
+
+* You can't use .rdb and AOF files generated with 2.6 into a 2.4 instance.
+* 2.6 slaves can be attached to 2.4 masters, but not the contrary, and only
+ for the time needed to perform the version upgrade.
+
+There are also a few API differences, that are unlikely to cause problems,
+but it is better to keep them in mind:
+
+* SORT now will refuse to sort in numerical mode elements that can't be parsed
+ as numbers.
+* EXPIREs now all have millisecond resolution (but this is very unlikely to
+ break code that was not conceived exploting the previous resolution error
+ in some way.)
+* INFO output is a bit different now, and contains empty lines and comments
+ starting with '#'. All the major clients should be already fixed to work
+ with the new INFO format.
+* Slaves are only read-only by default (but you can change this easily
+ setting the "slave-read-only" configuration option to "no" editing your
+ redis.conf or using CONFIG SET.
+
+The following INFO fields were renamed for consistency:
+
+ changes_since_last_save -> rdb_changes_since_last_save
+ bgsave_in_progress -> rdb_bgsave_in_progress
+ last_save_time -> rdb_last_save_time
+ last_bgsave_status -> rdb_last_bgsave_status
+ bgrewriteaof_in_progress -> aof_rewrite_in_progress
+ bgrewriteaof_scheduled -> aof_rewrite_scheduled
+
+The following redis.conf and CONFIG GET / SET parameters changed:
+
+ * hash-max-zipmap-entries, now replaced by hash-max-ziplist-entries
+ * hash-max-zipmap-value, now replaced by hash-max-ziplist-value
+ * glueoutputbuf option was now completely removed (was deprecated)
--------------------------------------------------------------------------------