michael@0: Following are change highlights associated with official releases.  Important
michael@0: bug fixes are all mentioned, but internal enhancements are omitted here for
michael@0: brevity (even though they are more fun to write about).  Much more detail can be
michael@0: found in the git revision history:
michael@0: 
michael@0:     http://www.canonware.com/cgi-bin/gitweb.cgi?p=jemalloc.git
michael@0:     git://canonware.com/jemalloc.git
michael@0: 
michael@0: * 3.x.x (Not yet released)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix "arenas.extend" mallctl to output the number of arenas.
michael@0: 
michael@0: * 3.2.0 (November 9, 2012)
michael@0: 
michael@0:   In addition to a couple of bug fixes, this version modifies page run
michael@0:   allocation and dirty page purging algorithms in order to better control
michael@0:   page-level virtual memory fragmentation.
michael@0: 
michael@0:   Incompatible changes:
michael@0:   - Change the "opt.lg_dirty_mult" default from 5 to 3 (32:1 to 8:1).
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix dss/mmap allocation precedence code to use recyclable mmap memory only
michael@0:     after primary dss allocation fails.
michael@0:   - Fix deadlock in the "arenas.purge" mallctl.  This regression was introduced
michael@0:     in 3.1.0 by the addition of the "arena.<i>.purge" mallctl.
michael@0: 
michael@0: * 3.1.0 (October 16, 2012)
michael@0: 
michael@0:   New features:
michael@0:   - Auto-detect whether running inside Valgrind, thus removing the need to
michael@0:     manually specify MALLOC_CONF=valgrind:true.
michael@0:   - Add the "arenas.extend" mallctl, which allows applications to create
michael@0:     manually managed arenas.
michael@0:   - Add the ALLOCM_ARENA() flag for {,r,d}allocm().
michael@0:   - Add the "opt.dss", "arena.<i>.dss", and "stats.arenas.<i>.dss" mallctls,
michael@0:     which provide control over dss/mmap precedence.
michael@0:   - Add the "arena.<i>.purge" mallctl, which obsoletes "arenas.purge".
michael@0:   - Define LG_QUANTUM for hppa.
michael@0: 
michael@0:   Incompatible changes:
michael@0:   - Disable tcache by default if running inside Valgrind, in order to avoid
michael@0:     making unallocated objects appear reachable to Valgrind.
michael@0:   - Drop const from malloc_usable_size() argument on Linux.
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix heap profiling crash if sampled object is freed via realloc(p, 0).
michael@0:   - Remove const from __*_hook variable declarations, so that glibc can modify
michael@0:     them during process forking.
michael@0:   - Fix mlockall(2)/madvise(2) interaction.
michael@0:   - Fix fork(2)-related deadlocks.
michael@0:   - Fix error return value for "thread.tcache.enabled" mallctl.
michael@0: 
michael@0: * 3.0.0 (May 11, 2012)
michael@0: 
michael@0:   Although this version adds some major new features, the primary focus is on
michael@0:   internal code cleanup that facilitates maintainability and portability, most
michael@0:   of which is not reflected in the ChangeLog.  This is the first release to
michael@0:   incorporate substantial contributions from numerous other developers, and the
michael@0:   result is a more broadly useful allocator (see the git revision history for
michael@0:   contribution details).  Note that the license has been unified, thanks to
michael@0:   Facebook granting a license under the same terms as the other copyright
michael@0:   holders (see COPYING).
michael@0: 
michael@0:   New features:
michael@0:   - Implement Valgrind support, redzones, and quarantine.
michael@0:   - Add support for additional platforms:
michael@0:     + FreeBSD
michael@0:     + Mac OS X Lion
michael@0:     + MinGW
michael@0:     + Windows (no support yet for replacing the system malloc)
michael@0:   - Add support for additional architectures:
michael@0:     + MIPS
michael@0:     + SH4
michael@0:     + Tilera
michael@0:   - Add support for cross compiling.
michael@0:   - Add nallocm(), which rounds a request size up to the nearest size class
michael@0:     without actually allocating.
michael@0:   - Implement aligned_alloc() (blame C11).
michael@0:   - Add the "thread.tcache.enabled" mallctl.
michael@0:   - Add the "opt.prof_final" mallctl.
michael@0:   - Update pprof (from gperftools 2.0).
michael@0:   - Add the --with-mangling option.
michael@0:   - Add the --disable-experimental option.
michael@0:   - Add the --disable-munmap option, and make it the default on Linux.
michael@0:   - Add the --enable-mremap option, which disables use of mremap(2) by default.
michael@0: 
michael@0:   Incompatible changes:
michael@0:   - Enable stats by default.
michael@0:   - Enable fill by default.
michael@0:   - Disable lazy locking by default.
michael@0:   - Rename the "tcache.flush" mallctl to "thread.tcache.flush".
michael@0:   - Rename the "arenas.pagesize" mallctl to "arenas.page".
michael@0:   - Change the "opt.lg_prof_sample" default from 0 to 19 (1 B to 512 KiB).
michael@0:   - Change the "opt.prof_accum" default from true to false.
michael@0: 
michael@0:   Removed features:
michael@0:   - Remove the swap feature, including the "config.swap", "swap.avail",
michael@0:     "swap.prezeroed", "swap.nfds", and "swap.fds" mallctls.
michael@0:   - Remove highruns statistics, including the
michael@0:     "stats.arenas.<i>.bins.<j>.highruns" and
michael@0:     "stats.arenas.<i>.lruns.<j>.highruns" mallctls.
michael@0:   - As part of small size class refactoring, remove the "opt.lg_[qc]space_max",
michael@0:     "arenas.cacheline", "arenas.subpage", "arenas.[tqcs]space_{min,max}", and
michael@0:     "arenas.[tqcs]bins" mallctls.
michael@0:   - Remove the "arenas.chunksize" mallctl.
michael@0:   - Remove the "opt.lg_prof_tcmax" option.
michael@0:   - Remove the "opt.lg_prof_bt_max" option.
michael@0:   - Remove the "opt.lg_tcache_gc_sweep" option.
michael@0:   - Remove the --disable-tiny option, including the "config.tiny" mallctl.
michael@0:   - Remove the --enable-dynamic-page-shift configure option.
michael@0:   - Remove the --enable-sysv configure option.
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix a statistics-related bug in the "thread.arena" mallctl that could cause
michael@0:     invalid statistics and crashes.
michael@0:   - Work around TLS deallocation via free() on Linux.  This bug could cause
michael@0:     write-after-free memory corruption.
michael@0:   - Fix a potential deadlock that could occur during interval- and
michael@0:     growth-triggered heap profile dumps.
michael@0:   - Fix large calloc() zeroing bugs due to dropping chunk map unzeroed flags.
michael@0:   - Fix chunk_alloc_dss() to stop claiming memory is zeroed.  This bug could
michael@0:     cause memory corruption and crashes with --enable-dss specified.
michael@0:   - Fix fork-related bugs that could cause deadlock in children between fork
michael@0:     and exec.
michael@0:   - Fix malloc_stats_print() to honor 'b' and 'l' in the opts parameter.
michael@0:   - Fix realloc(p, 0) to act like free(p).
michael@0:   - Do not enforce minimum alignment in memalign().
michael@0:   - Check for NULL pointer in malloc_usable_size().
michael@0:   - Fix an off-by-one heap profile statistics bug that could be observed in
michael@0:     interval- and growth-triggered heap profiles.
michael@0:   - Fix the "epoch" mallctl to update cached stats even if the passed in epoch
michael@0:     is 0.
michael@0:   - Fix bin->runcur management to fix a layout policy bug.  This bug did not
michael@0:     affect correctness.
michael@0:   - Fix a bug in choose_arena_hard() that potentially caused more arenas to be
michael@0:     initialized than necessary.
michael@0:   - Add missing "opt.lg_tcache_max" mallctl implementation.
michael@0:   - Use glibc allocator hooks to make mixed allocator usage less likely.
michael@0:   - Fix build issues for --disable-tcache.
michael@0:   - Don't mangle pthread_create() when --with-private-namespace is specified.
michael@0: 
michael@0: * 2.2.5 (November 14, 2011)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix huge_ralloc() race when using mremap(2).  This is a serious bug that
michael@0:     could cause memory corruption and/or crashes.
michael@0:   - Fix huge_ralloc() to maintain chunk statistics.
michael@0:   - Fix malloc_stats_print(..., "a") output.
michael@0: 
michael@0: * 2.2.4 (November 5, 2011)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Initialize arenas_tsd before using it.  This bug existed for 2.2.[0-3], as
michael@0:     well as for --disable-tls builds in earlier releases.
michael@0:   - Do not assume a 4 KiB page size in test/rallocm.c.
michael@0: 
michael@0: * 2.2.3 (August 31, 2011)
michael@0: 
michael@0:   This version fixes numerous bugs related to heap profiling.
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix a prof-related race condition.  This bug could cause memory corruption,
michael@0:     but only occurred in non-default configurations (prof_accum:false).
michael@0:   - Fix off-by-one backtracing issues (make sure that prof_alloc_prep() is
michael@0:     excluded from backtraces).
michael@0:   - Fix a prof-related bug in realloc() (only triggered by OOM errors).
michael@0:   - Fix prof-related bugs in allocm() and rallocm().
michael@0:   - Fix prof_tdata_cleanup() for --disable-tls builds.
michael@0:   - Fix a relative include path, to fix objdir builds.
michael@0: 
michael@0: * 2.2.2 (July 30, 2011)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix a build error for --disable-tcache.
michael@0:   - Fix assertions in arena_purge() (for real this time).
michael@0:   - Add the --with-private-namespace option.  This is a workaround for symbol
michael@0:     conflicts that can inadvertently arise when using static libraries.
michael@0: 
michael@0: * 2.2.1 (March 30, 2011)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Implement atomic operations for x86/x64.  This fixes compilation failures
michael@0:     for versions of gcc that are still in wide use.
michael@0:   - Fix an assertion in arena_purge().
michael@0: 
michael@0: * 2.2.0 (March 22, 2011)
michael@0: 
michael@0:   This version incorporates several improvements to algorithms and data
michael@0:   structures that tend to reduce fragmentation and increase speed.
michael@0: 
michael@0:   New features:
michael@0:   - Add the "stats.cactive" mallctl.
michael@0:   - Update pprof (from google-perftools 1.7).
michael@0:   - Improve backtracing-related configuration logic, and add the
michael@0:     --disable-prof-libgcc option.
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Change default symbol visibility from "internal", to "hidden", which
michael@0:     decreases the overhead of library-internal function calls.
michael@0:   - Fix symbol visibility so that it is also set on OS X.
michael@0:   - Fix a build dependency regression caused by the introduction of the .pic.o
michael@0:     suffix for PIC object files.
michael@0:   - Add missing checks for mutex initialization failures.
michael@0:   - Don't use libgcc-based backtracing except on x64, where it is known to work.
michael@0:   - Fix deadlocks on OS X that were due to memory allocation in
michael@0:     pthread_mutex_lock().
michael@0:   - Heap profiling-specific fixes:
michael@0:     + Fix memory corruption due to integer overflow in small region index
michael@0:       computation, when using a small enough sample interval that profiling
michael@0:       context pointers are stored in small run headers.
michael@0:     + Fix a bootstrap ordering bug that only occurred with TLS disabled.
michael@0:     + Fix a rallocm() rsize bug.
michael@0:     + Fix error detection bugs for aligned memory allocation.
michael@0: 
michael@0: * 2.1.3 (March 14, 2011)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix a cpp logic regression (due to the "thread.{de,}allocatedp" mallctl fix
michael@0:     for OS X in 2.1.2).
michael@0:   - Fix a "thread.arena" mallctl bug.
michael@0:   - Fix a thread cache stats merging bug.
michael@0: 
michael@0: * 2.1.2 (March 2, 2011)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix "thread.{de,}allocatedp" mallctl for OS X.
michael@0:   - Add missing jemalloc.a to build system.
michael@0: 
michael@0: * 2.1.1 (January 31, 2011)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix aligned huge reallocation (affected allocm()).
michael@0:   - Fix the ALLOCM_LG_ALIGN macro definition.
michael@0:   - Fix a heap dumping deadlock.
michael@0:   - Fix a "thread.arena" mallctl bug.
michael@0: 
michael@0: * 2.1.0 (December 3, 2010)
michael@0: 
michael@0:   This version incorporates some optimizations that can't quite be considered
michael@0:   bug fixes.
michael@0: 
michael@0:   New features:
michael@0:   - Use Linux's mremap(2) for huge object reallocation when possible.
michael@0:   - Avoid locking in mallctl*() when possible.
michael@0:   - Add the "thread.[de]allocatedp" mallctl's.
michael@0:   - Convert the manual page source from roff to DocBook, and generate both roff
michael@0:     and HTML manuals.
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix a crash due to incorrect bootstrap ordering.  This only impacted
michael@0:     --enable-debug --enable-dss configurations.
michael@0:   - Fix a minor statistics bug for mallctl("swap.avail", ...).
michael@0: 
michael@0: * 2.0.1 (October 29, 2010)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix a race condition in heap profiling that could cause undefined behavior
michael@0:     if "opt.prof_accum" were disabled.
michael@0:   - Add missing mutex unlocks for some OOM error paths in the heap profiling
michael@0:     code.
michael@0:   - Fix a compilation error for non-C99 builds.
michael@0: 
michael@0: * 2.0.0 (October 24, 2010)
michael@0: 
michael@0:   This version focuses on the experimental *allocm() API, and on improved
michael@0:   run-time configuration/introspection.  Nonetheless, numerous performance
michael@0:   improvements are also included.
michael@0: 
michael@0:   New features:
michael@0:   - Implement the experimental {,r,s,d}allocm() API, which provides a superset
michael@0:     of the functionality available via malloc(), calloc(), posix_memalign(),
michael@0:     realloc(), malloc_usable_size(), and free().  These functions can be used to
michael@0:     allocate/reallocate aligned zeroed memory, ask for optional extra memory
michael@0:     during reallocation, prevent object movement during reallocation, etc.
michael@0:   - Replace JEMALLOC_OPTIONS/JEMALLOC_PROF_PREFIX with MALLOC_CONF, which is
michael@0:     more human-readable, and more flexible.  For example:
michael@0:       JEMALLOC_OPTIONS=AJP
michael@0:     is now:
michael@0:       MALLOC_CONF=abort:true,fill:true,stats_print:true
michael@0:   - Port to Apple OS X.  Sponsored by Mozilla.
michael@0:   - Make it possible for the application to control thread-->arena mappings via
michael@0:     the "thread.arena" mallctl.
michael@0:   - Add compile-time support for all TLS-related functionality via pthreads TSD.
michael@0:     This is mainly of interest for OS X, which does not support TLS, but has a
michael@0:     TSD implementation with similar performance.
michael@0:   - Override memalign() and valloc() if they are provided by the system.
michael@0:   - Add the "arenas.purge" mallctl, which can be used to synchronously purge all
michael@0:     dirty unused pages.
michael@0:   - Make cumulative heap profiling data optional, so that it is possible to
michael@0:     limit the amount of memory consumed by heap profiling data structures.
michael@0:   - Add per thread allocation counters that can be accessed via the
michael@0:     "thread.allocated" and "thread.deallocated" mallctls.
michael@0: 
michael@0:   Incompatible changes:
michael@0:   - Remove JEMALLOC_OPTIONS and malloc_options (see MALLOC_CONF above).
michael@0:   - Increase default backtrace depth from 4 to 128 for heap profiling.
michael@0:   - Disable interval-based profile dumps by default.
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Remove bad assertions in fork handler functions.  These assertions could
michael@0:     cause aborts for some combinations of configure settings.
michael@0:   - Fix strerror_r() usage to deal with non-standard semantics in GNU libc.
michael@0:   - Fix leak context reporting.  This bug tended to cause the number of contexts
michael@0:     to be underreported (though the reported number of objects and bytes were
michael@0:     correct).
michael@0:   - Fix a realloc() bug for large in-place growing reallocation.  This bug could
michael@0:     cause memory corruption, but it was hard to trigger.
michael@0:   - Fix an allocation bug for small allocations that could be triggered if
michael@0:     multiple threads raced to create a new run of backing pages.
michael@0:   - Enhance the heap profiler to trigger samples based on usable size, rather
michael@0:     than request size.
michael@0:   - Fix a heap profiling bug due to sometimes losing track of requested object
michael@0:     size for sampled objects.
michael@0: 
michael@0: * 1.0.3 (August 12, 2010)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix the libunwind-based implementation of stack backtracing (used for heap
michael@0:     profiling).  This bug could cause zero-length backtraces to be reported.
michael@0:   - Add a missing mutex unlock in library initialization code.  If multiple
michael@0:     threads raced to initialize malloc, some of them could end up permanently
michael@0:     blocked.
michael@0: 
michael@0: * 1.0.2 (May 11, 2010)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix junk filling of large objects, which could cause memory corruption.
michael@0:   - Add MAP_NORESERVE support for chunk mapping, because otherwise virtual
michael@0:     memory limits could cause swap file configuration to fail.  Contributed by
michael@0:     Jordan DeLong.
michael@0: 
michael@0: * 1.0.1 (April 14, 2010)
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Fix compilation when --enable-fill is specified.
michael@0:   - Fix threads-related profiling bugs that affected accuracy and caused memory
michael@0:     to be leaked during thread exit.
michael@0:   - Fix dirty page purging race conditions that could cause crashes.
michael@0:   - Fix crash in tcache flushing code during thread destruction.
michael@0: 
michael@0: * 1.0.0 (April 11, 2010)
michael@0: 
michael@0:   This release focuses on speed and run-time introspection.  Numerous
michael@0:   algorithmic improvements make this release substantially faster than its
michael@0:   predecessors.
michael@0: 
michael@0:   New features:
michael@0:   - Implement autoconf-based configuration system.
michael@0:   - Add mallctl*(), for the purposes of introspection and run-time
michael@0:     configuration.
michael@0:   - Make it possible for the application to manually flush a thread's cache, via
michael@0:     the "tcache.flush" mallctl.
michael@0:   - Base maximum dirty page count on proportion of active memory.
michael@0:   - Compute various addtional run-time statistics, including per size class
michael@0:     statistics for large objects.
michael@0:   - Expose malloc_stats_print(), which can be called repeatedly by the
michael@0:     application.
michael@0:   - Simplify the malloc_message() signature to only take one string argument,
michael@0:     and incorporate an opaque data pointer argument for use by the application
michael@0:     in combination with malloc_stats_print().
michael@0:   - Add support for allocation backed by one or more swap files, and allow the
michael@0:     application to disable over-commit if swap files are in use.
michael@0:   - Implement allocation profiling and leak checking.
michael@0: 
michael@0:   Removed features:
michael@0:   - Remove the dynamic arena rebalancing code, since thread-specific caching
michael@0:     reduces its utility.
michael@0: 
michael@0:   Bug fixes:
michael@0:   - Modify chunk allocation to work when address space layout randomization
michael@0:     (ASLR) is in use.
michael@0:   - Fix thread cleanup bugs related to TLS destruction.
michael@0:   - Handle 0-size allocation requests in posix_memalign().
michael@0:   - Fix a chunk leak.  The leaked chunks were never touched, so this impacted
michael@0:     virtual memory usage, but not physical memory usage.
michael@0: 
michael@0: * linux_2008082[78]a (August 27/28, 2008)
michael@0: 
michael@0:   These snapshot releases are the simple result of incorporating Linux-specific
michael@0:   support into the FreeBSD malloc sources.
michael@0: 
michael@0: --------------------------------------------------------------------------------
michael@0: vim:filetype=text:textwidth=80