xref: /freebsd/contrib/jemalloc/ChangeLog (revision 84dfba8d183d31e3412639ecb4b8ad4433cf7e80)
1Following are change highlights associated with official releases.  Important
2bug fixes are all mentioned, but internal enhancements are omitted here for
3brevity (even though they are more fun to write about).  Much more detail can be
4found in the git revision history:
5
6    http://www.canonware.com/cgi-bin/gitweb.cgi?p=jemalloc.git
7    git://canonware.com/jemalloc.git
8
9* 3.4.1 (October 20, 2013)
10
11  Bug fixes:
12  - Fix a race in the "arenas.extend" mallctl that could cause memory corruption
13    of internal data structures and subsequent crashes.
14  - Fix Valgrind integration flaws that caused Valgrind warnings about reads of
15    uninitialized memory in:
16    + arena chunk headers
17    + internal zero-initialized data structures (relevant to tcache and prof
18      code)
19  - Preserve errno during the first allocation.  A readlink(2) call during
20    initialization fails unless /etc/malloc.conf exists, so errno was typically
21    set during the first allocation prior to this fix.
22  - Fix compilation warnings reported by gcc 4.8.1.
23
24* 3.4.0 (June 2, 2013)
25
26  This version is essentially a small bugfix release, but the addition of
27  aarch64 support requires that the minor version be incremented.
28
29  Bug fixes:
30  - Fix race-triggered deadlocks in chunk_record().  These deadlocks were
31    typically triggered by multiple threads concurrently deallocating huge
32    objects.
33
34  New features:
35  - Add support for the aarch64 architecture.
36
37* 3.3.1 (March 6, 2013)
38
39  This version fixes bugs that are typically encountered only when utilizing
40  custom run-time options.
41
42  Bug fixes:
43  - Fix a locking order bug that could cause deadlock during fork if heap
44    profiling were enabled.
45  - Fix a chunk recycling bug that could cause the allocator to lose track of
46    whether a chunk was zeroed.  On FreeBSD, NetBSD, and OS X, it could cause
47    corruption if allocating via sbrk(2) (unlikely unless running with the
48    "dss:primary" option specified).  This was completely harmless on Linux
49    unless using mlockall(2) (and unlikely even then, unless the
50    --disable-munmap configure option or the "dss:primary" option was
51    specified).  This regression was introduced in 3.1.0 by the
52    mlockall(2)/madvise(2) interaction fix.
53  - Fix TLS-related memory corruption that could occur during thread exit if the
54    thread never allocated memory.  Only the quarantine and prof facilities were
55    susceptible.
56  - Fix two quarantine bugs:
57    + Internal reallocation of the quarantined object array leaked the old
58      array.
59    + Reallocation failure for internal reallocation of the quarantined object
60      array (very unlikely) resulted in memory corruption.
61  - Fix Valgrind integration to annotate all internally allocated memory in a
62    way that keeps Valgrind happy about internal data structure access.
63  - Fix building for s390 systems.
64
65* 3.3.0 (January 23, 2013)
66
67  This version includes a few minor performance improvements in addition to the
68  listed new features and bug fixes.
69
70  New features:
71  - Add clipping support to lg_chunk option processing.
72  - Add the --enable-ivsalloc option.
73  - Add the --without-export option.
74  - Add the --disable-zone-allocator option.
75
76  Bug fixes:
77  - Fix "arenas.extend" mallctl to output the number of arenas.
78  - Fix chunk_recycle() to unconditionally inform Valgrind that returned memory
79    is undefined.
80  - Fix build break on FreeBSD related to alloca.h.
81
82* 3.2.0 (November 9, 2012)
83
84  In addition to a couple of bug fixes, this version modifies page run
85  allocation and dirty page purging algorithms in order to better control
86  page-level virtual memory fragmentation.
87
88  Incompatible changes:
89  - Change the "opt.lg_dirty_mult" default from 5 to 3 (32:1 to 8:1).
90
91  Bug fixes:
92  - Fix dss/mmap allocation precedence code to use recyclable mmap memory only
93    after primary dss allocation fails.
94  - Fix deadlock in the "arenas.purge" mallctl.  This regression was introduced
95    in 3.1.0 by the addition of the "arena.<i>.purge" mallctl.
96
97* 3.1.0 (October 16, 2012)
98
99  New features:
100  - Auto-detect whether running inside Valgrind, thus removing the need to
101    manually specify MALLOC_CONF=valgrind:true.
102  - Add the "arenas.extend" mallctl, which allows applications to create
103    manually managed arenas.
104  - Add the ALLOCM_ARENA() flag for {,r,d}allocm().
105  - Add the "opt.dss", "arena.<i>.dss", and "stats.arenas.<i>.dss" mallctls,
106    which provide control over dss/mmap precedence.
107  - Add the "arena.<i>.purge" mallctl, which obsoletes "arenas.purge".
108  - Define LG_QUANTUM for hppa.
109
110  Incompatible changes:
111  - Disable tcache by default if running inside Valgrind, in order to avoid
112    making unallocated objects appear reachable to Valgrind.
113  - Drop const from malloc_usable_size() argument on Linux.
114
115  Bug fixes:
116  - Fix heap profiling crash if sampled object is freed via realloc(p, 0).
117  - Remove const from __*_hook variable declarations, so that glibc can modify
118    them during process forking.
119  - Fix mlockall(2)/madvise(2) interaction.
120  - Fix fork(2)-related deadlocks.
121  - Fix error return value for "thread.tcache.enabled" mallctl.
122
123* 3.0.0 (May 11, 2012)
124
125  Although this version adds some major new features, the primary focus is on
126  internal code cleanup that facilitates maintainability and portability, most
127  of which is not reflected in the ChangeLog.  This is the first release to
128  incorporate substantial contributions from numerous other developers, and the
129  result is a more broadly useful allocator (see the git revision history for
130  contribution details).  Note that the license has been unified, thanks to
131  Facebook granting a license under the same terms as the other copyright
132  holders (see COPYING).
133
134  New features:
135  - Implement Valgrind support, redzones, and quarantine.
136  - Add support for additional platforms:
137    + FreeBSD
138    + Mac OS X Lion
139    + MinGW
140    + Windows (no support yet for replacing the system malloc)
141  - Add support for additional architectures:
142    + MIPS
143    + SH4
144    + Tilera
145  - Add support for cross compiling.
146  - Add nallocm(), which rounds a request size up to the nearest size class
147    without actually allocating.
148  - Implement aligned_alloc() (blame C11).
149  - Add the "thread.tcache.enabled" mallctl.
150  - Add the "opt.prof_final" mallctl.
151  - Update pprof (from gperftools 2.0).
152  - Add the --with-mangling option.
153  - Add the --disable-experimental option.
154  - Add the --disable-munmap option, and make it the default on Linux.
155  - Add the --enable-mremap option, which disables use of mremap(2) by default.
156
157  Incompatible changes:
158  - Enable stats by default.
159  - Enable fill by default.
160  - Disable lazy locking by default.
161  - Rename the "tcache.flush" mallctl to "thread.tcache.flush".
162  - Rename the "arenas.pagesize" mallctl to "arenas.page".
163  - Change the "opt.lg_prof_sample" default from 0 to 19 (1 B to 512 KiB).
164  - Change the "opt.prof_accum" default from true to false.
165
166  Removed features:
167  - Remove the swap feature, including the "config.swap", "swap.avail",
168    "swap.prezeroed", "swap.nfds", and "swap.fds" mallctls.
169  - Remove highruns statistics, including the
170    "stats.arenas.<i>.bins.<j>.highruns" and
171    "stats.arenas.<i>.lruns.<j>.highruns" mallctls.
172  - As part of small size class refactoring, remove the "opt.lg_[qc]space_max",
173    "arenas.cacheline", "arenas.subpage", "arenas.[tqcs]space_{min,max}", and
174    "arenas.[tqcs]bins" mallctls.
175  - Remove the "arenas.chunksize" mallctl.
176  - Remove the "opt.lg_prof_tcmax" option.
177  - Remove the "opt.lg_prof_bt_max" option.
178  - Remove the "opt.lg_tcache_gc_sweep" option.
179  - Remove the --disable-tiny option, including the "config.tiny" mallctl.
180  - Remove the --enable-dynamic-page-shift configure option.
181  - Remove the --enable-sysv configure option.
182
183  Bug fixes:
184  - Fix a statistics-related bug in the "thread.arena" mallctl that could cause
185    invalid statistics and crashes.
186  - Work around TLS deallocation via free() on Linux.  This bug could cause
187    write-after-free memory corruption.
188  - Fix a potential deadlock that could occur during interval- and
189    growth-triggered heap profile dumps.
190  - Fix large calloc() zeroing bugs due to dropping chunk map unzeroed flags.
191  - Fix chunk_alloc_dss() to stop claiming memory is zeroed.  This bug could
192    cause memory corruption and crashes with --enable-dss specified.
193  - Fix fork-related bugs that could cause deadlock in children between fork
194    and exec.
195  - Fix malloc_stats_print() to honor 'b' and 'l' in the opts parameter.
196  - Fix realloc(p, 0) to act like free(p).
197  - Do not enforce minimum alignment in memalign().
198  - Check for NULL pointer in malloc_usable_size().
199  - Fix an off-by-one heap profile statistics bug that could be observed in
200    interval- and growth-triggered heap profiles.
201  - Fix the "epoch" mallctl to update cached stats even if the passed in epoch
202    is 0.
203  - Fix bin->runcur management to fix a layout policy bug.  This bug did not
204    affect correctness.
205  - Fix a bug in choose_arena_hard() that potentially caused more arenas to be
206    initialized than necessary.
207  - Add missing "opt.lg_tcache_max" mallctl implementation.
208  - Use glibc allocator hooks to make mixed allocator usage less likely.
209  - Fix build issues for --disable-tcache.
210  - Don't mangle pthread_create() when --with-private-namespace is specified.
211
212* 2.2.5 (November 14, 2011)
213
214  Bug fixes:
215  - Fix huge_ralloc() race when using mremap(2).  This is a serious bug that
216    could cause memory corruption and/or crashes.
217  - Fix huge_ralloc() to maintain chunk statistics.
218  - Fix malloc_stats_print(..., "a") output.
219
220* 2.2.4 (November 5, 2011)
221
222  Bug fixes:
223  - Initialize arenas_tsd before using it.  This bug existed for 2.2.[0-3], as
224    well as for --disable-tls builds in earlier releases.
225  - Do not assume a 4 KiB page size in test/rallocm.c.
226
227* 2.2.3 (August 31, 2011)
228
229  This version fixes numerous bugs related to heap profiling.
230
231  Bug fixes:
232  - Fix a prof-related race condition.  This bug could cause memory corruption,
233    but only occurred in non-default configurations (prof_accum:false).
234  - Fix off-by-one backtracing issues (make sure that prof_alloc_prep() is
235    excluded from backtraces).
236  - Fix a prof-related bug in realloc() (only triggered by OOM errors).
237  - Fix prof-related bugs in allocm() and rallocm().
238  - Fix prof_tdata_cleanup() for --disable-tls builds.
239  - Fix a relative include path, to fix objdir builds.
240
241* 2.2.2 (July 30, 2011)
242
243  Bug fixes:
244  - Fix a build error for --disable-tcache.
245  - Fix assertions in arena_purge() (for real this time).
246  - Add the --with-private-namespace option.  This is a workaround for symbol
247    conflicts that can inadvertently arise when using static libraries.
248
249* 2.2.1 (March 30, 2011)
250
251  Bug fixes:
252  - Implement atomic operations for x86/x64.  This fixes compilation failures
253    for versions of gcc that are still in wide use.
254  - Fix an assertion in arena_purge().
255
256* 2.2.0 (March 22, 2011)
257
258  This version incorporates several improvements to algorithms and data
259  structures that tend to reduce fragmentation and increase speed.
260
261  New features:
262  - Add the "stats.cactive" mallctl.
263  - Update pprof (from google-perftools 1.7).
264  - Improve backtracing-related configuration logic, and add the
265    --disable-prof-libgcc option.
266
267  Bug fixes:
268  - Change default symbol visibility from "internal", to "hidden", which
269    decreases the overhead of library-internal function calls.
270  - Fix symbol visibility so that it is also set on OS X.
271  - Fix a build dependency regression caused by the introduction of the .pic.o
272    suffix for PIC object files.
273  - Add missing checks for mutex initialization failures.
274  - Don't use libgcc-based backtracing except on x64, where it is known to work.
275  - Fix deadlocks on OS X that were due to memory allocation in
276    pthread_mutex_lock().
277  - Heap profiling-specific fixes:
278    + Fix memory corruption due to integer overflow in small region index
279      computation, when using a small enough sample interval that profiling
280      context pointers are stored in small run headers.
281    + Fix a bootstrap ordering bug that only occurred with TLS disabled.
282    + Fix a rallocm() rsize bug.
283    + Fix error detection bugs for aligned memory allocation.
284
285* 2.1.3 (March 14, 2011)
286
287  Bug fixes:
288  - Fix a cpp logic regression (due to the "thread.{de,}allocatedp" mallctl fix
289    for OS X in 2.1.2).
290  - Fix a "thread.arena" mallctl bug.
291  - Fix a thread cache stats merging bug.
292
293* 2.1.2 (March 2, 2011)
294
295  Bug fixes:
296  - Fix "thread.{de,}allocatedp" mallctl for OS X.
297  - Add missing jemalloc.a to build system.
298
299* 2.1.1 (January 31, 2011)
300
301  Bug fixes:
302  - Fix aligned huge reallocation (affected allocm()).
303  - Fix the ALLOCM_LG_ALIGN macro definition.
304  - Fix a heap dumping deadlock.
305  - Fix a "thread.arena" mallctl bug.
306
307* 2.1.0 (December 3, 2010)
308
309  This version incorporates some optimizations that can't quite be considered
310  bug fixes.
311
312  New features:
313  - Use Linux's mremap(2) for huge object reallocation when possible.
314  - Avoid locking in mallctl*() when possible.
315  - Add the "thread.[de]allocatedp" mallctl's.
316  - Convert the manual page source from roff to DocBook, and generate both roff
317    and HTML manuals.
318
319  Bug fixes:
320  - Fix a crash due to incorrect bootstrap ordering.  This only impacted
321    --enable-debug --enable-dss configurations.
322  - Fix a minor statistics bug for mallctl("swap.avail", ...).
323
324* 2.0.1 (October 29, 2010)
325
326  Bug fixes:
327  - Fix a race condition in heap profiling that could cause undefined behavior
328    if "opt.prof_accum" were disabled.
329  - Add missing mutex unlocks for some OOM error paths in the heap profiling
330    code.
331  - Fix a compilation error for non-C99 builds.
332
333* 2.0.0 (October 24, 2010)
334
335  This version focuses on the experimental *allocm() API, and on improved
336  run-time configuration/introspection.  Nonetheless, numerous performance
337  improvements are also included.
338
339  New features:
340  - Implement the experimental {,r,s,d}allocm() API, which provides a superset
341    of the functionality available via malloc(), calloc(), posix_memalign(),
342    realloc(), malloc_usable_size(), and free().  These functions can be used to
343    allocate/reallocate aligned zeroed memory, ask for optional extra memory
344    during reallocation, prevent object movement during reallocation, etc.
345  - Replace JEMALLOC_OPTIONS/JEMALLOC_PROF_PREFIX with MALLOC_CONF, which is
346    more human-readable, and more flexible.  For example:
347      JEMALLOC_OPTIONS=AJP
348    is now:
349      MALLOC_CONF=abort:true,fill:true,stats_print:true
350  - Port to Apple OS X.  Sponsored by Mozilla.
351  - Make it possible for the application to control thread-->arena mappings via
352    the "thread.arena" mallctl.
353  - Add compile-time support for all TLS-related functionality via pthreads TSD.
354    This is mainly of interest for OS X, which does not support TLS, but has a
355    TSD implementation with similar performance.
356  - Override memalign() and valloc() if they are provided by the system.
357  - Add the "arenas.purge" mallctl, which can be used to synchronously purge all
358    dirty unused pages.
359  - Make cumulative heap profiling data optional, so that it is possible to
360    limit the amount of memory consumed by heap profiling data structures.
361  - Add per thread allocation counters that can be accessed via the
362    "thread.allocated" and "thread.deallocated" mallctls.
363
364  Incompatible changes:
365  - Remove JEMALLOC_OPTIONS and malloc_options (see MALLOC_CONF above).
366  - Increase default backtrace depth from 4 to 128 for heap profiling.
367  - Disable interval-based profile dumps by default.
368
369  Bug fixes:
370  - Remove bad assertions in fork handler functions.  These assertions could
371    cause aborts for some combinations of configure settings.
372  - Fix strerror_r() usage to deal with non-standard semantics in GNU libc.
373  - Fix leak context reporting.  This bug tended to cause the number of contexts
374    to be underreported (though the reported number of objects and bytes were
375    correct).
376  - Fix a realloc() bug for large in-place growing reallocation.  This bug could
377    cause memory corruption, but it was hard to trigger.
378  - Fix an allocation bug for small allocations that could be triggered if
379    multiple threads raced to create a new run of backing pages.
380  - Enhance the heap profiler to trigger samples based on usable size, rather
381    than request size.
382  - Fix a heap profiling bug due to sometimes losing track of requested object
383    size for sampled objects.
384
385* 1.0.3 (August 12, 2010)
386
387  Bug fixes:
388  - Fix the libunwind-based implementation of stack backtracing (used for heap
389    profiling).  This bug could cause zero-length backtraces to be reported.
390  - Add a missing mutex unlock in library initialization code.  If multiple
391    threads raced to initialize malloc, some of them could end up permanently
392    blocked.
393
394* 1.0.2 (May 11, 2010)
395
396  Bug fixes:
397  - Fix junk filling of large objects, which could cause memory corruption.
398  - Add MAP_NORESERVE support for chunk mapping, because otherwise virtual
399    memory limits could cause swap file configuration to fail.  Contributed by
400    Jordan DeLong.
401
402* 1.0.1 (April 14, 2010)
403
404  Bug fixes:
405  - Fix compilation when --enable-fill is specified.
406  - Fix threads-related profiling bugs that affected accuracy and caused memory
407    to be leaked during thread exit.
408  - Fix dirty page purging race conditions that could cause crashes.
409  - Fix crash in tcache flushing code during thread destruction.
410
411* 1.0.0 (April 11, 2010)
412
413  This release focuses on speed and run-time introspection.  Numerous
414  algorithmic improvements make this release substantially faster than its
415  predecessors.
416
417  New features:
418  - Implement autoconf-based configuration system.
419  - Add mallctl*(), for the purposes of introspection and run-time
420    configuration.
421  - Make it possible for the application to manually flush a thread's cache, via
422    the "tcache.flush" mallctl.
423  - Base maximum dirty page count on proportion of active memory.
424  - Compute various addtional run-time statistics, including per size class
425    statistics for large objects.
426  - Expose malloc_stats_print(), which can be called repeatedly by the
427    application.
428  - Simplify the malloc_message() signature to only take one string argument,
429    and incorporate an opaque data pointer argument for use by the application
430    in combination with malloc_stats_print().
431  - Add support for allocation backed by one or more swap files, and allow the
432    application to disable over-commit if swap files are in use.
433  - Implement allocation profiling and leak checking.
434
435  Removed features:
436  - Remove the dynamic arena rebalancing code, since thread-specific caching
437    reduces its utility.
438
439  Bug fixes:
440  - Modify chunk allocation to work when address space layout randomization
441    (ASLR) is in use.
442  - Fix thread cleanup bugs related to TLS destruction.
443  - Handle 0-size allocation requests in posix_memalign().
444  - Fix a chunk leak.  The leaked chunks were never touched, so this impacted
445    virtual memory usage, but not physical memory usage.
446
447* linux_2008082[78]a (August 27/28, 2008)
448
449  These snapshot releases are the simple result of incorporating Linux-specific
450  support into the FreeBSD malloc sources.
451
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