ChangeLog

2015-09-01  Cache Team <cache-team@twitter.com>
	* twemcache: version 2.6.2 release
	* Feature: adding "config maxbytes" command to adjust heap
	* Feature: adding socket, memory, and context switch related stats
	* Feature: adding max reporting for all gauges
	* Fix: port signal handler patch from twemproxy
	* Fix: update item_expire for flushed items
	* Fix: updating settings.verbose when verbosity level changes
	* Fix: adding long option form of -e
	* Misc: changing default number of workers from 4 to 2
	* Misc: downsizing default connection buffer
	* Misc: lower ac requirements; making -rdynamic linux only
	* Misc: added coverage support; COVERAGE.md for instructions

2013-06-04  Cache Team <cache-team@twitter.com>
	* twemcache: version 2.6.0 release
	* Fix: memory leak in suffix, with contribution from @ferlatum & @skuzmich
	* Fix: mc_cache create using the right parameter now (credit to @haipome)
	* Fix: wrong assertion crippling debug version of binary
	* Fix: UDP packet using 100% CPU (backported by @cloudflare)
	* Feature: adding separate metrics to track get* commands and get* keys
	* Feature: adding appendrl and prepend rl command to return data length
	* Cleanup: avoiding allocating item/slab magic when assert is not used
	* Cleanup: stats cleanup within the item & command processing modules
	* Cleanup: refactoring of the interfaces between mc_items.* and mc_ascii.*
	* Misc: help information now displays in Unix style

2012-12-11  Cache Team <cache-team@twitter.com>
	* twemcache: version 2.5.3 release
	* Fix: insufficient item length causing segfault
	* Fix: get/delete race causing segfault
	* Fix: inconsistency in prepend/append replies under concurrency
	* Fix: update cas for in-place prepend/append
	* Fix: strtoull function taking length as a parameter to avoid overrun
	* Debug: memory-scrubbing enabled in full debug build
	* Misc: soarpenguin's several from https://github.com/twitter/twemcache/pull/15

2012-09-24  Cache Team <cache-team@twitter.com>
	* twemcache: version 2.5.2 release
	* Feature: command line option for klog sampling rate, default is now 100
	* Fix: garbled data in suffix
	* Performance: avoid all unnecessary memcpy in processing prepend/apprend

2012-09-06  Cache Team <cache-team@twitter.com>
	* twemcache: version 2.5.1 release
	* Feature: slab LRC eviction (-M 8), designed for write through cases
	* Feature: auto klog rotation support, reopen after size reaches 1GB
	           klog is turned on if a filename is given at start time
	* Feature: Backporting fixed size (-e) hash feature from memcached 1.4.8
	* Cleanup: data flags and data length now stored as part of item header
	* Misc: updated TODO list

2012-07-16  Cache Team <cache-team@twitter.com>
	* twemcache: version 2.5.0 release
	* Feature: slab LRU eviction (-M 4) introduced
	           multiple eviction strategies can now be stacked
	* Fix: fix logical error of code and remove meaningless code (monadbobo)
	* Misc: new notes, updated TODO list
	        add twctop README

2012-07-10  Cache Team <cache-team@twitter.com>

	* twemcache: version 2.4.0 release
	  twemcache is the twitter memcached

2009-04-10

	* *critical bugfix*. In 1.2.7 under multithreaded mode, memcached
	  would never restart accepting connections after hitting the
	  maximum connection limit.

2009-04-02

	* Fix: Rewrote stat buffer handling (Trond)

2009-03-31

	* Feature:  -b option for configuring backlog

	* Feature:  stats settings

	* Fix: binary stat alignment bug (bug26)

	* Fix: buffer overflow in stats (bug27)

	* Fix: recycle memory more aggressively (bug14)

	* Fix: incr validation (bug31)

	* Fix: 64-bit incr/decr delta problem (bug21)

	* Fix: Ascii UDP set (bug36)

	* Fix: stats slabs' used chunks (bug29)

	* Fix: stats reset resetting more (bug22)

	* Misc: More tests, documentation, cleanliness (godliness)

	* Stable merge (stats, debuggability, listen bugs)

2009-03-11

	* Protocol:  Binary complete (Dustin, Trond, Toru, etc...)

	* Performance:  improvements from facebook (Dormando)

	* Performance:  per-thread stats (Trond)

	* Performance:  Hash expansion in its own thread (Trond)

	* Stats:  Lots of new stats (Dustin)

	* Bug fixes (various)

	See the 1.3.2 release notes or revision control for more detail.

2008-09-06

	* Display error status on listen failures (Dormando)

	* Remove managed instance code. Incomplete/etc. (Dormando)

	* Handle broken IPV6 stacks better (Brian Aker)

	* Generate warnings on setsockopt() failures (Brian Aker)

	* Fix some indentation issues (Brian Aker)

	* UDP/TCP can be disabled by setting their port to zero (Brian Aker)

	* Zero out libevent thread structures before use (Ricky Zhou)

	* New stat: Last accessed time for last evicted item per slab class.
         (Dormando)

	* Use a dedicated socket accept thread (Facebook)

	* Add -R option. Limit the number of requests processed by a connection
          at once. Prevents starving other threads if bulk loading. (Facebook)

2008-07 [Version 1.2.6 released]

2008-07-24 [Version 1.2.6-rc1 released]

	* Add support for newer automake (Facebook)

	* DTrace support for Solaris/etc (Trond Norbye)

	* LRU tests (Steve Yen)

	* Handle negative length items properly (Dormando)

	* Don't leave stale data after failed set attempts (Dormando)

	* Fix refcount leaks, which would result in OOM's on all sets
	  (Dormando)

	* Fix buffer overruns (Dustin Sallings, Tomash Brechko)

	* Fix memory corruption with CAS (Dustin Sallings)

2008-06-11

	* Fix -k to work with -d. (reported by Gary Zhu)

2008-03-02 [Version 1.2.5-rc1 released]

	* Add per-item-class tracking of evictions and OOM errors (dormando)

	* Optimize item_alloc() a little (dormando)

	* Give 'SERVER_ERROR out of memory' errors more context (dormando)

	* Enable usage of large memory pages under solaris
          (Trond.Norbye@Sun.COM)

	* Enable UDP by default, clean up server socket code
          (brian@tangent.org)

	* 'noreply' support (Tomash Brechko)

	* IPv6 support, and IPv6 multi-interface support (brian@tangent.org)

	* Add compiler options for Sun Studio compilers with --enable-threads
	  (Trond.Norbye@Sun.COM)

	* Add --enable-64bit for mulitarget platforms (Trond.Norbye@Sun.COM)

	* Use gettimeofday(2) instead of time(2).

	* Make -k option work (Tomash Brechko)

	* Fix chunk slab alignment (Trond.Norbye@Sun.COM)

2007-12-06 [Version 1.2.4 released]

2007-12-05

	* Fix compilation on panther (JS and Dormando)

	* More CAS tests (Chris Goffinet)

	* Final fixes for all 1.2.4 features are in, -rc2 sent out.

2007-11-19 [Version 1.2.4-rc1 released]

2007-11-19  Dormando <dormando@rydia.net>

	* Patch series from Tomash Brechko <tomash.brechko@gmail.com>:
	  Minor fixes and optimisations.

	* Patches from Chris, Dustin, and Dormando to fix CAS.

	* Prepping for 1.2.4 release.

2007-11-13  Dormando <dormando@rydia.net>

	* Adjusted patch from js <ebgssth@gmail.com>: Compile on OS X Panther
	  and earlier.

2007-11-12  Steven Grimm  <sgrimm@facebook.com>

	* Patch from Tomash Brechko <tomash.brechko@gmail.com>: Always send
	  "SERVER_ERROR out of memory" when memory exhausted.

2007-10-15  Paul Lindner  <lindner@inuus.com>

	* Patch from David Bremner <bremner@unb.ca> that implements
	  a new option "-a" which takes an octal permission mask
	  (like chmod) sets the permissions on the unix domain socket
	  (specified by "-s").

2007-10-03 Paul Lindner <lindner@inuus.com>
	* Incorporate "cas" operation developed by Dustin
	  Sallings <dustin@spy.net> This change allows you
	  to do atomic changes to an existing key.

	* Fix for stats.evictions not incrementing
	  when exptime == 0 items are kicked off the cache.
	  from Jean-Francois BUSTARRET <jfbustarret@wat.tv>.

	* Fix for do_item_cachedump() which was returning
	  an incorrect timestamp.

	* Switch to unsigned 64-bit increment/decrement counters
	  from Evan Miller and Dustin Sallings.

	* Add append command support written by Filipe Laborde.
	  Thread safe version plus prepend command from Maxim Dounin
	  <mdounin@mdounin.ru>

	* The memcached-tool script can now display stats.  Patch
	  provided by Dan Christian <dchristian@google.com>

	* Fix for Unix Domain sockets on FreeBSD
	  FreeBSD's sendmsg() requires msg_name in msghdr structure
	  to be NULL if not used, setting msg_namelen to 0 isn't enough.
	  Patch from Maxim Dounin <mdounin@mdounin.ru>

2007-08-21 Paul Lindner <lindner@inuus.com>

	* Incorporate incrememnt patch from Evan Miller
	  <emiller@imvu.com> to define increment overflow
	  behavior.

2007-08-07 Leon Brocard <acme@astray.com>

	* Bring the memcached.1 manpage up to date

2007-08-06 Paul Lindner <lindner@inuus.com>

	* Fix crash when using -P and -d flags on x86_64
	  with latest libevent release.

2007-07-08  Steven Grimm  <sgrimm@facebook.com>

	* Item stats commands weren't thread-safe; wrap them with locks
	  when compiled in multithreaded mode.

	* The "stats items" command now works again; it broke with the
	  introduction of the powers-of-N chunk size change.

2007-07-06 [Version 1.2.3 released]

2007-06-19  Paul Lindner  <lindner@mirth.inuus.com>

	* Solaris portability fixes from Trond Norbye

2007-05-29  Paul Lindner  <lindner@mirth.inuus.com>

	* Properly document evictions statistic value

2007-05-10  Paul Lindner  <lindner@inuus.com>

	* Flesh out tests for unix domain sockets and binary data.

	* Update rpm spec file to run tests

2007-05-07  Paul Lindner  <lindner@inuus.com>

	* Fix compilation bug on freebsd 6.x (and maybe others)

	* Update RPM spec file per redhat bugzilla #238994

	* Move unistd.h to memcached.h to get rid of warnings

	* Add string.h to thread.c to get correctly prototyped strerror()

2007-05-04  Paul Lindner  <lindner@inuus.com>

	* Add fedora/redhat style init script and RPM spec file

2007-05-12 [Version 1.2.2 released]

2007-04-16  Steven Grimm  <sgrimm@facebook.com>

	* Command tokenizer performance and cleanliness improvement.
	  Patch contributed by Paolo Borelli <paolo.borelli@gmail.com>.

2007-04-16  Paul Lindner  <lindner@inuus.com>

	* Add notes to README about MacOS, libevent and kqueue.

	* Windows Patch integration -- part 1, warnings elimination.

2007-04-12  Paul Lindner  <lindner@mirth.inuus.com>

	* Allow changes to the verbosity level of the server with a new
	  "verbosity" command and some compiler cleanups.
          Patch contributed by Paolo Borelli <paolo.borelli@gmail.com>.

2007-04-08  Paul Lindner  <lindner@inuus.com>

	* Add cleanup patch from "Tim Yardley" <liquid@haveheart.com> to
	  clean up source spacing issues, fix -Wall warnings, add some
	  null checks, adds asserts at the top of each function for any
	  use of conn *c without checking to see if c is NULL first.

        * Also adjust clean-whitespace.pl to clean *.ac files.  Add
          script to test-suite to test for tabs.

2007-04-04  Paul Lindner  <lindner@inuus.com>

	* Add clarification of flush_all in the protocol docs
	  from Elizabeth Mattijsen <liz@dijkmat.nl>

2007-03-31  Paul Lindner  <lindner@inuus.com>

	* Add patch from Eli Bingham <eli@pandora.com> to
	  re-enable the -n switch to memcached.

2007-03-20  Paul Lindner  <lindner@inuus.com>

	* Add patch to collect eviction statistics from
          Jean-Francois BUSTARRET <jfbustarret@wat.tv>.

        * Updated docs, added new test cases for t/stats.t

2007-03-18  Paul Lindner  <lindner@inuus.com>

	* Add more test cases using larger buffer sizes up to and greater
	  than 1MB.

	* Remove unused parameter to item_size_ok()

	* Use a single printf() in usage()

	* Add a failing test for conforming with maximum connections.

2007-03-17

	* crash fix from Thomas van Gulick <thomas@partyflock.nl> in
	  conn_shrink(), passing &ptr, instead of ptr to realloc().

2007-03-05  Paul Lindner  <lindner@inuus.com>

	* Fix a number of places where (s)printf calls were using unsigned
	  or signed formats that did not match their arguments.

	* Add support for stdbool.h and stdint.h to use the bool and
	  uint8_t types.

	* Major refactoring - move API calls for assoc/items/slabs to
	  their own individual header files.  Add apropriate const and
	  static declarations as appropriate.

	* Avoid type-punning.  Do a more efficient realloc inside the
	  conn_shrink routine.

        * Fix overflow bug where uninitialized access to slabclass caused
	  size-0 mallocs during slab preallocation.

	* Use EXIT_SUCCESS/EXIT_FAILURE constants.

	* Convert some sprintf calls to snprintf to protect against
	  buffer overflows.

	* Explicitly compare against NULL or zero in many places.

2007-03-05

	* Steven Grimm <sgrimm@facebook.com>: Per-object-type stats collection
	  support. Specify the object type delimiter with the -D command line
	  option. Turn stats gathering on and off with "stats detail on" and
	  "stats detail off". Dump the per-object-type details with
	  "stats detail dump".

2007-03-01

	* Steven Grimm <sgrimm@facebook.com>: Fix an off-by-one error in the
	  multithreaded version's message passing code.

2006-12-23

	* Fix expirations of items set with absolute expiration times in
	  the past, before the server's start time.  bug was introduced in
	  1.2.0 with rel_time_t.  Thanks to Adam Dixon
	  <adamtdixon@gmail.com> for the bug report and test case!

2006-11-26

	* Steven Grimm <sgrimm@facebook.com>: Performance improvements:

	  Dynamic sizing of hashtable to reduce collisions on very large
	  caches and conserve memory on small caches.

	  Only reposition items in the LRU queue once a minute, to reduce
	  overhead of accessing extremely frequently-used items.

	  Stop listening for new connections until an existing one closes
	  if we run out of available file descriptors.

	  Command parser refactoring: Add a single-pass tokenizer to cut
	  down on string scanning.  Split the command processing into
	  separate functions for easier profiling and better readability.
	  Pass key lengths along with the keys in all API functions that
	  need keys, to avoid needing to call strlen() repeatedly.

2006-11-25

	* Steve Peters <steve@fisharerojo.org>: OpenBSD has a malloc.h,
	  but warns to use stdlib.h instead

2006-11-22

	* Steven Grimm <sgrimm@facebook.com>: Add support for multithreaded
	  execution. Run configure with "--enable-threads" to enable. See
	  doc/threads.txt for details.

2006-11-13

	* Iain Wade <iwade@optusnet.com.au>: Fix for UDP responses on non-"get"
	 commands.

2006-10-15

	* Steven Grimm <sgrimm@facebook.com>: Dynamic sizing of hashtable to
	  reduce collisions on very large caches and conserve memory on
	  small caches.

2006-10-13

	* Steven Grimm <sgrimm@facebook.com>: New faster hash function.

2006-09-20

	* don't listen on UDP by default; more clear message when UDP port in use

2006-09-09

	* release 1.2.0 (along with 1.1.13, which is the more tested branch)

	  nobody has run 1.2.0 in production, to my knowledge.  facebook has run
	  their pre-merge-with-trunk version, but bugs were discovered (and fixed)
	  after the merge.  there might be more.  you've been warned.  :)

2006-09-04

	* improved autoconf libevent detection, from the Tor project.

2006-09-03

	* test suite and lot of expiration, delete, flush_all, etc corner
	  case bugs fixed (Brad Fitzpatrick)

2006-09-02

	* Nathan Neulinger <nneul@umr.edu>: fix breakage in expiration code
	  causing expiration times to not be processed correctly.

2006-08-21

	* Nathan Neulinger <nneul@umr.edu>: fix incompatabilities with
	  unix domain socket support and the UDP code and clean up stale
	  sockets

2006-08-20

	* Nathan Neulinger <nneul@umr.edu>: unix domain socket support

2006-05-03

	* Steven Grimm <sgrimm@facebook.com>:  big bunch of changes:
	  big CPU reduction work, UDP-based interface, increased memory
	  efficiency.  (intertwined patch, committed all together)
	  <http://lists.danga.com/pipermail/memcached/2006-May/002164.html>
	  or see svn commit logs

2006-04-30

	* River Tarnell:  autoconf work for Solaris 10.  Brad:
	  merge and verify it works on Nexenta.

2006-03-04

	* avva: bucket/generation patch (old, but Brad's just finally
	  committing it)

2006-01-01

	* Brad Fitzpatrick <brad@danga.com>:  allocate 1 slab per class
	  on start-up, to avoid confusing users with out-of-memory errors
	  later.  this is 18 MB of allocation on start, unless max memory
	  allowed with -m is lower, in which case only the smaller slab
	  classes are allocated.

2005-08-09

	* Elizabeth Mattijsen <liz@dijkmat.nl>: needed a way to flush all
	  memcached backend servers, but not at exactly the same time (to
	  reduce load peaks), I've added some simple functionality to the
	  memcached protocol in the "flush_all" command that allows you to
	  specify a time at which the flush will actually occur (instead of
	  always at the moment the "flush_all" command is received).

2005-05-25

	* patch from Peter van Dijk <peter@nextgear.nl> to make
	  stderr unbuffered, for running under daemontools

2005-04-04

	* patch from Don MacAskill <don@smugmug.com> 'flush_all' doesn't
	  seem to work properly.  Basically, if you try to add a key which
	  is present, but expired, the store fails but the old key is no
	  longer expired.

	* release 1.1.12

2005-01-14

	* Date: Thu, 18 Nov 2004 15:25:59 -0600
	  From: David Phillips <electrum@gmail.com>
	  Here is a patch to configure.ac and Makefile.am to put the man page in
	  the correct location.  Trying to install the man page from a
	  subdirectory results in the subdirectory being used in the install
	  path (it tries to install to doc/memcached.1).  This is the correct
	  thing to  do:

	- create a Makefile.am in the doc directory that installs the man page
	  with man_MANS
	- modify Makefile.am in the base directory to reference the doc
  	  directory using SUBDIRS
	- modify the AC_CONFIG_FILES macro in configure.ac to output the
	  Makefile in doc


2005-01-14

	* pidfile saving support from Lisa Seelye <lisa@gentoo.org>, sent
	  Jan 13, 2005

2005-01-14

	* don't delete libevent events that haven't been added (the deltimer)
	  patch from Ted Schundler <tschundler@gmail.com>

2004-12-10

	* document -M and -r in manpage (Doug Porter <dsp@dsp.name>)

2004-07-22

	* fix buffer overflow in items.c with 250 byte keys along with
	  other info on the same line going into a 256 byte char[].
	  thanks to Andrei Nigmatulin <anight@monamour.ru>

2004-06-15

	* immediate deletes weren't being unlinked a few seconds,
	  preventing "add" commands to the same key in that time period.
	  thanks to Michael Alan Dorman <mdorman@debian.org> for the
	  bug report and demo script.

2004-04-30

	* released 1.1.11

2004-04-24

	* Avva: Add a new command line option: -r , to maximize core file
	  limit.

2004-03-31

	* Avva: Use getrlimit and setrlimit to set limits for number of
	  simultaneously open file descriptors. Get the current limits and
	  try to raise them if they're not enough for the specified (or the
	  default) setting of max connections.

2004-02-24

	* Adds a '-M' flag to turn off tossing items from the cache.
	  (Jason Titus <jtitus@postini.com>)

2004-02-19 (Evan)

	* Install manpage on "make install", etc.

2003-12-30 (Brad)

	* remove static build stuff.  interferes with PAM setuid stuff
	  and was only included as a possible fix with the old memory
	  allocator.  really shouldn't make a difference.
	* add Jay Bonci's Debian scripts and manpage
	* release version 1.1.10

2003-12-01 (Avva)

	* New command: flush_all, causes all existing items to
	  be invalidated immediately (without deleting them from
	  memory, merely causing memcached to no longer return them).

2003-10-23

	* Shift init code around to fix daemon mode on FreeBSD,
	* and drop root only after creating the server socket (to
	* allow the use of privileged ports)
	* version 1.1.10pre

2003-10-09

	* BSD compile fixes from Ryan T. Dean
	* version 1.1.9

2003-09-29

	* ignore SIGPIPE at start instead of crashing in rare cases it
	  comes up.  no other code had to be modified, since everything
	  else is already dead-connection-aware.  (avva)

2003-09-09 (Avva, Lisa Marie Seelye <lisa@gentoo.org>)

	* setuid support

2003-09-05 (Avva)

	* accept all new connections in the same event (so we work with ET epoll)
	* mark all items as clsid=0 after slab page reassignment to please future
	  asserts (on the road to making slab page reassignment work fully)

2003-08-12 (Brad Fitzpatrick)

	* use TCP_CORK on Linux or TCP_PUSH on BSD
	* only use TCP_NODELAY when we don't have alternatives

2003-08-10

	* disable Nagel's Algorithm (TCP_NODELAY) for better performance (avva)

2003-08-10
	* support multiple levels of verbosity (-vv)

2003-08-10  (Evan Martin)

	* Makefile.am: debug, optimization, and static flags are controlled
	  by the configure script.
	* configure.ac:
	  - allow specifying libevent directory with --with-libevent=DIR
	  - check for malloc.h (unavailable on BSDs)
	  - check for socklen_t (unavailable on OSX)
	* assoc.c, items.c, slabs.c:  Remove some unused headers.
	* memcached.c:  allow for nonexistence of malloc.h; #define a POSIX
	  macro to import mlockall flags.

2003-07-29

	* version 1.1.7
	* big bug fix: item exptime 0 meant expire immediately, not never
	* version 1.1.8

2003-07-22

	* make 'delete' take second arg, of time to refuse new add/replace
	* set/add/replace/delete can all take abs or delta time (delta can't
	  be larger than a month)

2003-07-21

	* added doc/protocol.txt

2003-07-01

	* report CPU usage in stats

2003-06-30

	* version 1.1.6
	* fix a number of obscure bugs
	* more stats reporting

2003-06-10

	* removing use of Judy; use a hash.  (judy caused memory fragmentation)
	* shrink some structures
	* security improvements
	* version 1.1.0

2003-06-18

	* changing maxsize back to an unsigned int

2003-06-16

	* adding PHP support
	* added CONTRIBUTORS file
	* version 1.0.4

2003-06-15

	* forgot to distribute website/api (still learning auto*)
	* version 1.0.3

2003-06-15

	* update to version 1.0.2
	* autoconf/automake fixes for older versions
	* make stats report version number
	* change license from GPL to BSD

Fri, 13 Jun 2003 10:05:51 -0700  Evan Martin  <martine@danga.com>

	* configure.ac, autogen.sh, Makefile.am:  Use autotools.
	* items.c, memcached.c:  #include <time.h> for time(),
	  printf time_t as %lu (is this correct?),
	  minor warnings fixes.