00-RELEASENOTES

   1 Redis 2.6 release notes
   2
   3 Migrating from 2.4 to 2.6
   4 =========================
   5
   6 Redis 2.4 is mostly a strict subset of 2.6. However there are a few things
   7 that you should be aware of:
   8
   9 * You can't use .rdb and AOF files generated with 2.6 into a 2.4 instance.
  10 * 2.4 slaves can be attached to 2.6 masters, but not the contrary, and only
  11   for the time needed to perform the version upgrade.
  12
  13 There are also a few API differences, that are unlikely to cause problems,
  14 but it is better to keep them in mind:
  15
  16 * SORT now will refuse to sort in numerical mode elements that can't be parsed
  17   as numbers.
  18 * EXPIREs now all have millisecond resolution (but this is very unlikely to
  19   break code that was not conceived exploting the previous resolution error
  20   in some way.)
  21 * INFO output is a bit different now, and contains empty lines and comments
  22   starting with '#'. All the major clients should be already fixed to work
  23   with the new INFO format.
  24 * Slaves are only read-only by default (but you can change this easily
  25   setting the "slave-read-only" configuration option to "no" editing your
  26   redis.conf or using CONFIG SET.
  27
  28 Also the following redis.conf and CONFIG GET / SET parameters changed name:
  29
  30     * hash-max-zipmap-entries, now replaced by hash-max-ziplist-entries
  31     * hash-max-zipmap-value, now replaced by hash-max-ziplist-value
  32     * glueoutputbuf option was now completely removed (was deprecated)
  33
  34 ---------
  35 CHANGELOG
  36 ---------
  37
  38 What's new in Redis 2.5.9 (aka 2.6 Release Candidate 3)
  39 =======================================================
  40
  41 UPGRADE URGENCY: critical, upgrade ASAP.
  42
  43 * [BUGFIX] Fix for issue #500 (https://github.com/antirez/redis/pull/500).
  44            Redis 2.6-RC1 and RC2 may corrupt ziplist-encoded sorted sets
  45            produced by Redis 2.4.x.
  46 * [BUGFIX] Fixed several bugs in init.d script.
  47 * [BUGFIX] syncio.c functions modified for speed and correctness. On osx
  48            (and possibly other BSD-based systems) the slave would block on
  49            replication to send the SYNC command when the master was not
  50            available. This is fixed now, but was not affecting Linux installs.
  51 * Now when slave-serve-stale-data is set to yes and the master is down, instead
  52   of reporting a generic error Redis replies with -MASTERDOWN.
  53
  54 What's new in Redis 2.5.8 (aka 2.6 Release Candidate 2)
  55 =======================================================
  56
  57 UPGRADE URGENCY: high for all the users of the KEYS command, otherwise low.
  58
  59 * [BUGFIX] Fix for KEYS command: if the DB contains keys with expires the KEYS
  60            command may return the wrong output, having duplicated or missing
  61            keys. See issue #487 and #488 on github for details.
  62
  63 What's new in Redis 2.5.7 (aka 2.6 Release Candidate 1)
  64 =======================================================
  65
  66 UPGRADE URGENCY: upgrade not recommended because this is an RC release.
  67
  68 * This is the first release candidate for Redis 2.6. We are not aware of
  69   bugs, but part of this code is young and was never tested in production
  70   environments, so handle with care.
  71
  72 An overview of new features and changes in Redis 2.6.x
  73 ======================================================
  74
  75 * Server side Lua scripting, see http://redis.io/commands/eval
  76 * Virtual Memory removed (was deprecated in 2.4)
  77 * Hardcoded limits about max number of clients removed.
  78 * AOF low level semantics is generally more sane, and especially when used
  79   in slaves.
  80 * Milliseconds resolution expires, also added new commands with milliseconds
  81   precision (PEXPIRE, PTTL, ...).
  82 * Better memory usage for "small" lists, ziplists and hashes when fields or
  83   values contain small integers.
  84 * Read only slaves.
  85 * Clients max output buffer soft and hard limits. You can specifiy different
  86   limits for different classes of clients (normal,pubsub,slave).
  87 * AOF is now able to rewrite aggregate data types using variadic commands,
  88   often producing an AOF that is faster to save, load, and is smaller in size.
  89 * Every redis.conf directive is now accepted as a command line option for the
  90   redis-server binary, with the same name and number of arguments.
  91 * Hash table seed randomization for protection against collisions attacks.
  92 * Performances improved when writing large objects to Redis.
  93 * Integrated memory test, see redis-server --test-memory.
  94 * INCRBYFLOAT and HINCRBYFLOAT commands.
  95 * New DUMP, RESTORE, MIGRATE commands (back ported from Redis Cluster to 2.6).
  96 * CRC64 checksump in RDB files.
  97 * Better MONITOR output and behavior (now commands are logged before execution).
  98 * "Software Watchdog" feature to debug latency issues.
  99 * Significant parts of the core refactored or rewritten. New internal APIs
 100   and core changes allowed to develop Redis Cluster on top of the new code,
 101   however for 2.6 all the cluster code was removed, and will be released with
 102   Redis 3.0 when it is more complete and stable.
 103 * Redis ASCII art logo added at startup.
 104 * Crash report on memory violation or failed asserts improved significantly
 105   to make debugging of hard to catch bugs simpler.
 106 * redis-benchmark improvements: ability to run selected tests,
 107   CSV output, faster, better help.
 108 * redis-cli improvements: --eval for comfortable development of Lua scripts.
 109 * SHUTDOWN now supports two optional arguments: "SAVE" and "NOSAVE".
 110 * INFO output split into sections, the command is now able to just show
 111   pecific sections.
 112 * New statistics about how many time a command was called, and how much
 113   execution time it used (INFO commandstats).
 114 * More predictable SORT behavior in edge cases.
 115 * Better support for big endian and *BSD systems.
 116 * Build system improved.
 117
 118 --------------------------------------------------------------------------------
 119
 120 Credits: Where not specified the implementation and design are done by
 121 Salvatore Sanfilippo and Pieter Noordhuis. Thanks to VMware for making all
 122 this possible. Also many thanks to all the other contributors and the amazing
 123 community we have.
 124
 125 See commit messages for more credits.
 126
 127 Cheers,
 128 Salvatore