1 Following are change highlights associated with official releases. Important 2 bug fixes are all mentioned, but some internal enhancements are omitted here for 3 brevity. Much more detail can be found in the git revision history: 4 5 https://github.com/jemalloc/jemalloc 6 7 * 4.4.0 (December 3, 2016) 8 9 New features: 10 - Add configure support for *-*-linux-android. (@cferris1000, @jasone) 11 - Add the --disable-syscall configure option, for use on systems that place 12 security-motivated limitations on syscall(2). (@jasone) 13 - Add support for Debian GNU/kFreeBSD. (@thesam) 14 15 Optimizations: 16 - Add extent serial numbers and use them where appropriate as a sort key that 17 is higher priority than address, so that the allocation policy prefers older 18 extents. This tends to improve locality (decrease fragmentation) when 19 memory grows downward. (@jasone) 20 - Refactor madvise(2) configuration so that MADV_FREE is detected and utilized 21 on Linux 4.5 and newer. (@jasone) 22 - Mark partially purged arena chunks as non-huge-page. This improves 23 interaction with Linux's transparent huge page functionality. (@jasone) 24 25 Bug fixes: 26 - Fix size class computations for edge conditions involving extremely large 27 allocations. This regression was first released in 4.0.0. (@jasone, 28 @ingvarha) 29 - Remove overly restrictive assertions related to the cactive statistic. This 30 regression was first released in 4.1.0. (@jasone) 31 - Implement a more reliable detection scheme for os_unfair_lock on macOS. 32 (@jszakmeister) 33 34 * 4.3.1 (November 7, 2016) 35 36 Bug fixes: 37 - Fix a severe virtual memory leak. This regression was first released in 38 4.3.0. (@interwq, @jasone) 39 - Refactor atomic and prng APIs to restore support for 32-bit platforms that 40 use pre-C11 toolchains, e.g. FreeBSD's mips. (@jasone) 41 42 * 4.3.0 (November 4, 2016) 43 44 This is the first release that passes the test suite for multiple Windows 45 configurations, thanks in large part to @glandium setting up continuous 46 integration via AppVeyor (and Travis CI for Linux and OS X). 47 48 New features: 49 - Add "J" (JSON) support to malloc_stats_print(). (@jasone) 50 - Add Cray compiler support. (@ronawho) 51 52 Optimizations: 53 - Add/use adaptive spinning for bootstrapping and radix tree node 54 initialization. (@jasone) 55 56 Bug fixes: 57 - Fix large allocation to search starting in the optimal size class heap, 58 which can substantially reduce virtual memory churn and fragmentation. This 59 regression was first released in 4.0.0. (@mjp41, @jasone) 60 - Fix stats.arenas.<i>.nthreads accounting. (@interwq) 61 - Fix and simplify decay-based purging. (@jasone) 62 - Make DSS (sbrk(2)-related) operations lockless, which resolves potential 63 deadlocks during thread exit. (@jasone) 64 - Fix over-sized allocation of radix tree leaf nodes. (@mjp41, @ogaun, 65 @jasone) 66 - Fix over-sized allocation of arena_t (plus associated stats) data 67 structures. (@jasone, @interwq) 68 - Fix EXTRA_CFLAGS to not affect configuration. (@jasone) 69 - Fix a Valgrind integration bug. (@ronawho) 70 - Disallow 0x5a junk filling when running in Valgrind. (@jasone) 71 - Fix a file descriptor leak on Linux. This regression was first released in 72 4.2.0. (@vsarunas, @jasone) 73 - Fix static linking of jemalloc with glibc. (@djwatson) 74 - Use syscall(2) rather than {open,read,close}(2) during boot on Linux. This 75 works around other libraries' system call wrappers performing reentrant 76 allocation. (@kspinka, @Whissi, @jasone) 77 - Fix OS X default zone replacement to work with OS X 10.12. (@glandium, 78 @jasone) 79 - Fix cached memory management to avoid needless commit/decommit operations 80 during purging, which resolves permanent virtual memory map fragmentation 81 issues on Windows. (@mjp41, @jasone) 82 - Fix TSD fetches to avoid (recursive) allocation. This is relevant to 83 non-TLS and Windows configurations. (@jasone) 84 - Fix malloc_conf overriding to work on Windows. (@jasone) 85 - Forcibly disable lazy-lock on Windows (was forcibly *enabled*). (@jasone) 86 87 * 4.2.1 (June 8, 2016) 88 89 Bug fixes: 90 - Fix bootstrapping issues for configurations that require allocation during 91 tsd initialization (e.g. --disable-tls). (@cferris1000, @jasone) 92 - Fix gettimeofday() version of nstime_update(). (@ronawho) 93 - Fix Valgrind regressions in calloc() and chunk_alloc_wrapper(). (@ronawho) 94 - Fix potential VM map fragmentation regression. (@jasone) 95 - Fix opt_zero-triggered in-place huge reallocation zeroing. (@jasone) 96 - Fix heap profiling context leaks in reallocation edge cases. (@jasone) 97 98 * 4.2.0 (May 12, 2016) 99 100 New features: 101 - Add the arena.<i>.reset mallctl, which makes it possible to discard all of 102 an arena's allocations in a single operation. (@jasone) 103 - Add the stats.retained and stats.arenas.<i>.retained statistics. (@jasone) 104 - Add the --with-version configure option. (@jasone) 105 - Support --with-lg-page values larger than actual page size. (@jasone) 106 107 Optimizations: 108 - Use pairing heaps rather than red-black trees for various hot data 109 structures. (@djwatson, @jasone) 110 - Streamline fast paths of rtree operations. (@jasone) 111 - Optimize the fast paths of calloc() and [m,d,sd]allocx(). (@jasone) 112 - Decommit unused virtual memory if the OS does not overcommit. (@jasone) 113 - Specify MAP_NORESERVE on Linux if [heuristic] overcommit is active, in order 114 to avoid unfortunate interactions during fork(2). (@jasone) 115 116 Bug fixes: 117 - Fix chunk accounting related to triggering gdump profiles. (@jasone) 118 - Link against librt for clock_gettime(2) if glibc < 2.17. (@jasone) 119 - Scale leak report summary according to sampling probability. (@jasone) 120 121 * 4.1.1 (May 3, 2016) 122 123 This bugfix release resolves a variety of mostly minor issues, though the 124 bitmap fix is critical for 64-bit Windows. 125 126 Bug fixes: 127 - Fix the linear scan version of bitmap_sfu() to shift by the proper amount 128 even when sizeof(long) is not the same as sizeof(void *), as on 64-bit 129 Windows. (@jasone) 130 - Fix hashing functions to avoid unaligned memory accesses (and resulting 131 crashes). This is relevant at least to some ARM-based platforms. 132 (@rkmisra) 133 - Fix fork()-related lock rank ordering reversals. These reversals were 134 unlikely to cause deadlocks in practice except when heap profiling was 135 enabled and active. (@jasone) 136 - Fix various chunk leaks in OOM code paths. (@jasone) 137 - Fix malloc_stats_print() to print opt.narenas correctly. (@jasone) 138 - Fix MSVC-specific build/test issues. (@rustyx, @yuslepukhin) 139 - Fix a variety of test failures that were due to test fragility rather than 140 core bugs. (@jasone) 141 142 * 4.1.0 (February 28, 2016) 143 144 This release is primarily about optimizations, but it also incorporates a lot 145 of portability-motivated refactoring and enhancements. Many people worked on 146 this release, to an extent that even with the omission here of minor changes 147 (see git revision history), and of the people who reported and diagnosed 148 issues, so much of the work was contributed that starting with this release, 149 changes are annotated with author credits to help reflect the collaborative 150 effort involved. 151 152 New features: 153 - Implement decay-based unused dirty page purging, a major optimization with 154 mallctl API impact. This is an alternative to the existing ratio-based 155 unused dirty page purging, and is intended to eventually become the sole 156 purging mechanism. New mallctls: 157 + opt.purge 158 + opt.decay_time 159 + arena.<i>.decay 160 + arena.<i>.decay_time 161 + arenas.decay_time 162 + stats.arenas.<i>.decay_time 163 (@jasone, @cevans87) 164 - Add --with-malloc-conf, which makes it possible to embed a default 165 options string during configuration. This was motivated by the desire to 166 specify --with-malloc-conf=purge:decay , since the default must remain 167 purge:ratio until the 5.0.0 release. (@jasone) 168 - Add MS Visual Studio 2015 support. (@rustyx, @yuslepukhin) 169 - Make *allocx() size class overflow behavior defined. The maximum 170 size class is now less than PTRDIFF_MAX to protect applications against 171 numerical overflow, and all allocation functions are guaranteed to indicate 172 errors rather than potentially crashing if the request size exceeds the 173 maximum size class. (@jasone) 174 - jeprof: 175 + Add raw heap profile support. (@jasone) 176 + Add --retain and --exclude for backtrace symbol filtering. (@jasone) 177 178 Optimizations: 179 - Optimize the fast path to combine various bootstrapping and configuration 180 checks and execute more streamlined code in the common case. (@interwq) 181 - Use linear scan for small bitmaps (used for small object tracking). In 182 addition to speeding up bitmap operations on 64-bit systems, this reduces 183 allocator metadata overhead by approximately 0.2%. (@djwatson) 184 - Separate arena_avail trees, which substantially speeds up run tree 185 operations. (@djwatson) 186 - Use memoization (boot-time-computed table) for run quantization. Separate 187 arena_avail trees reduced the importance of this optimization. (@jasone) 188 - Attempt mmap-based in-place huge reallocation. This can dramatically speed 189 up incremental huge reallocation. (@jasone) 190 191 Incompatible changes: 192 - Make opt.narenas unsigned rather than size_t. (@jasone) 193 194 Bug fixes: 195 - Fix stats.cactive accounting regression. (@rustyx, @jasone) 196 - Handle unaligned keys in hash(). This caused problems for some ARM systems. 197 (@jasone, @cferris1000) 198 - Refactor arenas array. In addition to fixing a fork-related deadlock, this 199 makes arena lookups faster and simpler. (@jasone) 200 - Move retained memory allocation out of the default chunk allocation 201 function, to a location that gets executed even if the application installs 202 a custom chunk allocation function. This resolves a virtual memory leak. 203 (@buchgr) 204 - Fix a potential tsd cleanup leak. (@cferris1000, @jasone) 205 - Fix run quantization. In practice this bug had no impact unless 206 applications requested memory with alignment exceeding one page. 207 (@jasone, @djwatson) 208 - Fix LinuxThreads-specific bootstrapping deadlock. (Cosmin Paraschiv) 209 - jeprof: 210 + Don't discard curl options if timeout is not defined. (@djwatson) 211 + Detect failed profile fetches. (@djwatson) 212 - Fix stats.arenas.<i>.{dss,lg_dirty_mult,decay_time,pactive,pdirty} for 213 --disable-stats case. (@jasone) 214 215 * 4.0.4 (October 24, 2015) 216 217 This bugfix release fixes another xallocx() regression. No other regressions 218 have come to light in over a month, so this is likely a good starting point 219 for people who prefer to wait for "dot one" releases with all the major issues 220 shaken out. 221 222 Bug fixes: 223 - Fix xallocx(..., MALLOCX_ZERO to zero the last full trailing page of large 224 allocations that have been randomly assigned an offset of 0 when 225 --enable-cache-oblivious configure option is enabled. 226 227 * 4.0.3 (September 24, 2015) 228 229 This bugfix release continues the trend of xallocx() and heap profiling fixes. 230 231 Bug fixes: 232 - Fix xallocx(..., MALLOCX_ZERO) to zero all trailing bytes of large 233 allocations when --enable-cache-oblivious configure option is enabled. 234 - Fix xallocx(..., MALLOCX_ZERO) to zero trailing bytes of huge allocations 235 when resizing from/to a size class that is not a multiple of the chunk size. 236 - Fix prof_tctx_dump_iter() to filter out nodes that were created after heap 237 profile dumping started. 238 - Work around a potentially bad thread-specific data initialization 239 interaction with NPTL (glibc's pthreads implementation). 240 241 * 4.0.2 (September 21, 2015) 242 243 This bugfix release addresses a few bugs specific to heap profiling. 244 245 Bug fixes: 246 - Fix ixallocx_prof_sample() to never modify nor create sampled small 247 allocations. xallocx() is in general incapable of moving small allocations, 248 so this fix removes buggy code without loss of generality. 249 - Fix irallocx_prof_sample() to always allocate large regions, even when 250 alignment is non-zero. 251 - Fix prof_alloc_rollback() to read tdata from thread-specific data rather 252 than dereferencing a potentially invalid tctx. 253 254 * 4.0.1 (September 15, 2015) 255 256 This is a bugfix release that is somewhat high risk due to the amount of 257 refactoring required to address deep xallocx() problems. As a side effect of 258 these fixes, xallocx() now tries harder to partially fulfill requests for 259 optional extra space. Note that a couple of minor heap profiling 260 optimizations are included, but these are better thought of as performance 261 fixes that were integral to disovering most of the other bugs. 262 263 Optimizations: 264 - Avoid a chunk metadata read in arena_prof_tctx_set(), since it is in the 265 fast path when heap profiling is enabled. Additionally, split a special 266 case out into arena_prof_tctx_reset(), which also avoids chunk metadata 267 reads. 268 - Optimize irallocx_prof() to optimistically update the sampler state. The 269 prior implementation appears to have been a holdover from when 270 rallocx()/xallocx() functionality was combined as rallocm(). 271 272 Bug fixes: 273 - Fix TLS configuration such that it is enabled by default for platforms on 274 which it works correctly. 275 - Fix arenas_cache_cleanup() and arena_get_hard() to handle 276 allocation/deallocation within the application's thread-specific data 277 cleanup functions even after arenas_cache is torn down. 278 - Fix xallocx() bugs related to size+extra exceeding HUGE_MAXCLASS. 279 - Fix chunk purge hook calls for in-place huge shrinking reallocation to 280 specify the old chunk size rather than the new chunk size. This bug caused 281 no correctness issues for the default chunk purge function, but was 282 visible to custom functions set via the "arena.<i>.chunk_hooks" mallctl. 283 - Fix heap profiling bugs: 284 + Fix heap profiling to distinguish among otherwise identical sample sites 285 with interposed resets (triggered via the "prof.reset" mallctl). This bug 286 could cause data structure corruption that would most likely result in a 287 segfault. 288 + Fix irealloc_prof() to prof_alloc_rollback() on OOM. 289 + Make one call to prof_active_get_unlocked() per allocation event, and use 290 the result throughout the relevant functions that handle an allocation 291 event. Also add a missing check in prof_realloc(). These fixes protect 292 allocation events against concurrent prof_active changes. 293 + Fix ixallocx_prof() to pass usize_max and zero to ixallocx_prof_sample() 294 in the correct order. 295 + Fix prof_realloc() to call prof_free_sampled_object() after calling 296 prof_malloc_sample_object(). Prior to this fix, if tctx and old_tctx were 297 the same, the tctx could have been prematurely destroyed. 298 - Fix portability bugs: 299 + Don't bitshift by negative amounts when encoding/decoding run sizes in 300 chunk header maps. This affected systems with page sizes greater than 8 301 KiB. 302 + Rename index_t to szind_t to avoid an existing type on Solaris. 303 + Add JEMALLOC_CXX_THROW to the memalign() function prototype, in order to 304 match glibc and avoid compilation errors when including both 305 jemalloc/jemalloc.h and malloc.h in C++ code. 306 + Don't assume that /bin/sh is appropriate when running size_classes.sh 307 during configuration. 308 + Consider __sparcv9 a synonym for __sparc64__ when defining LG_QUANTUM. 309 + Link tests to librt if it contains clock_gettime(2). 310 311 * 4.0.0 (August 17, 2015) 312 313 This version contains many speed and space optimizations, both minor and 314 major. The major themes are generalization, unification, and simplification. 315 Although many of these optimizations cause no visible behavior change, their 316 cumulative effect is substantial. 317 318 New features: 319 - Normalize size class spacing to be consistent across the complete size 320 range. By default there are four size classes per size doubling, but this 321 is now configurable via the --with-lg-size-class-group option. Also add the 322 --with-lg-page, --with-lg-page-sizes, --with-lg-quantum, and 323 --with-lg-tiny-min options, which can be used to tweak page and size class 324 settings. Impacts: 325 + Worst case performance for incrementally growing/shrinking reallocation 326 is improved because there are far fewer size classes, and therefore 327 copying happens less often. 328 + Internal fragmentation is limited to 20% for all but the smallest size 329 classes (those less than four times the quantum). (1B + 4 KiB) 330 and (1B + 4 MiB) previously suffered nearly 50% internal fragmentation. 331 + Chunk fragmentation tends to be lower because there are fewer distinct run 332 sizes to pack. 333 - Add support for explicit tcaches. The "tcache.create", "tcache.flush", and 334 "tcache.destroy" mallctls control tcache lifetime and flushing, and the 335 MALLOCX_TCACHE(tc) and MALLOCX_TCACHE_NONE flags to the *allocx() API 336 control which tcache is used for each operation. 337 - Implement per thread heap profiling, as well as the ability to 338 enable/disable heap profiling on a per thread basis. Add the "prof.reset", 339 "prof.lg_sample", "thread.prof.name", "thread.prof.active", 340 "opt.prof_thread_active_init", "prof.thread_active_init", and 341 "thread.prof.active" mallctls. 342 - Add support for per arena application-specified chunk allocators, configured 343 via the "arena.<i>.chunk_hooks" mallctl. 344 - Refactor huge allocation to be managed by arenas, so that arenas now 345 function as general purpose independent allocators. This is important in 346 the context of user-specified chunk allocators, aside from the scalability 347 benefits. Related new statistics: 348 + The "stats.arenas.<i>.huge.allocated", "stats.arenas.<i>.huge.nmalloc", 349 "stats.arenas.<i>.huge.ndalloc", and "stats.arenas.<i>.huge.nrequests" 350 mallctls provide high level per arena huge allocation statistics. 351 + The "arenas.nhchunks", "arenas.hchunk.<i>.size", 352 "stats.arenas.<i>.hchunks.<j>.nmalloc", 353 "stats.arenas.<i>.hchunks.<j>.ndalloc", 354 "stats.arenas.<i>.hchunks.<j>.nrequests", and 355 "stats.arenas.<i>.hchunks.<j>.curhchunks" mallctls provide per size class 356 statistics. 357 - Add the 'util' column to malloc_stats_print() output, which reports the 358 proportion of available regions that are currently in use for each small 359 size class. 360 - Add "alloc" and "free" modes for for junk filling (see the "opt.junk" 361 mallctl), so that it is possible to separately enable junk filling for 362 allocation versus deallocation. 363 - Add the jemalloc-config script, which provides information about how 364 jemalloc was configured, and how to integrate it into application builds. 365 - Add metadata statistics, which are accessible via the "stats.metadata", 366 "stats.arenas.<i>.metadata.mapped", and 367 "stats.arenas.<i>.metadata.allocated" mallctls. 368 - Add the "stats.resident" mallctl, which reports the upper limit of 369 physically resident memory mapped by the allocator. 370 - Add per arena control over unused dirty page purging, via the 371 "arenas.lg_dirty_mult", "arena.<i>.lg_dirty_mult", and 372 "stats.arenas.<i>.lg_dirty_mult" mallctls. 373 - Add the "prof.gdump" mallctl, which makes it possible to toggle the gdump 374 feature on/off during program execution. 375 - Add sdallocx(), which implements sized deallocation. The primary 376 optimization over dallocx() is the removal of a metadata read, which often 377 suffers an L1 cache miss. 378 - Add missing header includes in jemalloc/jemalloc.h, so that applications 379 only have to #include <jemalloc/jemalloc.h>. 380 - Add support for additional platforms: 381 + Bitrig 382 + Cygwin 383 + DragonFlyBSD 384 + iOS 385 + OpenBSD 386 + OpenRISC/or1k 387 388 Optimizations: 389 - Maintain dirty runs in per arena LRUs rather than in per arena trees of 390 dirty-run-containing chunks. In practice this change significantly reduces 391 dirty page purging volume. 392 - Integrate whole chunks into the unused dirty page purging machinery. This 393 reduces the cost of repeated huge allocation/deallocation, because it 394 effectively introduces a cache of chunks. 395 - Split the arena chunk map into two separate arrays, in order to increase 396 cache locality for the frequently accessed bits. 397 - Move small run metadata out of runs, into arena chunk headers. This reduces 398 run fragmentation, smaller runs reduce external fragmentation for small size 399 classes, and packed (less uniformly aligned) metadata layout improves CPU 400 cache set distribution. 401 - Randomly distribute large allocation base pointer alignment relative to page 402 boundaries in order to more uniformly utilize CPU cache sets. This can be 403 disabled via the --disable-cache-oblivious configure option, and queried via 404 the "config.cache_oblivious" mallctl. 405 - Micro-optimize the fast paths for the public API functions. 406 - Refactor thread-specific data to reside in a single structure. This assures 407 that only a single TLS read is necessary per call into the public API. 408 - Implement in-place huge allocation growing and shrinking. 409 - Refactor rtree (radix tree for chunk lookups) to be lock-free, and make 410 additional optimizations that reduce maximum lookup depth to one or two 411 levels. This resolves what was a concurrency bottleneck for per arena huge 412 allocation, because a global data structure is critical for determining 413 which arenas own which huge allocations. 414 415 Incompatible changes: 416 - Replace --enable-cc-silence with --disable-cc-silence to suppress spurious 417 warnings by default. 418 - Assure that the constness of malloc_usable_size()'s return type matches that 419 of the system implementation. 420 - Change the heap profile dump format to support per thread heap profiling, 421 rename pprof to jeprof, and enhance it with the --thread=<n> option. As a 422 result, the bundled jeprof must now be used rather than the upstream 423 (gperftools) pprof. 424 - Disable "opt.prof_final" by default, in order to avoid atexit(3), which can 425 internally deadlock on some platforms. 426 - Change the "arenas.nlruns" mallctl type from size_t to unsigned. 427 - Replace the "stats.arenas.<i>.bins.<j>.allocated" mallctl with 428 "stats.arenas.<i>.bins.<j>.curregs". 429 - Ignore MALLOC_CONF in set{uid,gid,cap} binaries. 430 - Ignore MALLOCX_ARENA(a) in dallocx(), in favor of using the 431 MALLOCX_TCACHE(tc) and MALLOCX_TCACHE_NONE flags to control tcache usage. 432 433 Removed features: 434 - Remove the *allocm() API, which is superseded by the *allocx() API. 435 - Remove the --enable-dss options, and make dss non-optional on all platforms 436 which support sbrk(2). 437 - Remove the "arenas.purge" mallctl, which was obsoleted by the 438 "arena.<i>.purge" mallctl in 3.1.0. 439 - Remove the unnecessary "opt.valgrind" mallctl; jemalloc automatically 440 detects whether it is running inside Valgrind. 441 - Remove the "stats.huge.allocated", "stats.huge.nmalloc", and 442 "stats.huge.ndalloc" mallctls. 443 - Remove the --enable-mremap option. 444 - Remove the "stats.chunks.current", "stats.chunks.total", and 445 "stats.chunks.high" mallctls. 446 447 Bug fixes: 448 - Fix the cactive statistic to decrease (rather than increase) when active 449 memory decreases. This regression was first released in 3.5.0. 450 - Fix OOM handling in memalign() and valloc(). A variant of this bug existed 451 in all releases since 2.0.0, which introduced these functions. 452 - Fix an OOM-related regression in arena_tcache_fill_small(), which could 453 cause cache corruption on OOM. This regression was present in all releases 454 from 2.2.0 through 3.6.0. 455 - Fix size class overflow handling for malloc(), posix_memalign(), memalign(), 456 calloc(), and realloc() when profiling is enabled. 457 - Fix the "arena.<i>.dss" mallctl to return an error if "primary" or 458 "secondary" precedence is specified, but sbrk(2) is not supported. 459 - Fix fallback lg_floor() implementations to handle extremely large inputs. 460 - Ensure the default purgeable zone is after the default zone on OS X. 461 - Fix latent bugs in atomic_*(). 462 - Fix the "arena.<i>.dss" mallctl to handle read-only calls. 463 - Fix tls_model configuration to enable the initial-exec model when possible. 464 - Mark malloc_conf as a weak symbol so that the application can override it. 465 - Correctly detect glibc's adaptive pthread mutexes. 466 - Fix the --without-export configure option. 467 468 * 3.6.0 (March 31, 2014) 469 470 This version contains a critical bug fix for a regression present in 3.5.0 and 471 3.5.1. 472 473 Bug fixes: 474 - Fix a regression in arena_chunk_alloc() that caused crashes during 475 small/large allocation if chunk allocation failed. In the absence of this 476 bug, chunk allocation failure would result in allocation failure, e.g. NULL 477 return from malloc(). This regression was introduced in 3.5.0. 478 - Fix backtracing for gcc intrinsics-based backtracing by specifying 479 -fno-omit-frame-pointer to gcc. Note that the application (and all the 480 libraries it links to) must also be compiled with this option for 481 backtracing to be reliable. 482 - Use dss allocation precedence for huge allocations as well as small/large 483 allocations. 484 - Fix test assertion failure message formatting. This bug did not manifest on 485 x86_64 systems because of implementation subtleties in va_list. 486 - Fix inconsequential test failures for hash and SFMT code. 487 488 New features: 489 - Support heap profiling on FreeBSD. This feature depends on the proc 490 filesystem being mounted during heap profile dumping. 491 492 * 3.5.1 (February 25, 2014) 493 494 This version primarily addresses minor bugs in test code. 495 496 Bug fixes: 497 - Configure Solaris/Illumos to use MADV_FREE. 498 - Fix junk filling for mremap(2)-based huge reallocation. This is only 499 relevant if configuring with the --enable-mremap option specified. 500 - Avoid compilation failure if 'restrict' C99 keyword is not supported by the 501 compiler. 502 - Add a configure test for SSE2 rather than assuming it is usable on i686 503 systems. This fixes test compilation errors, especially on 32-bit Linux 504 systems. 505 - Fix mallctl argument size mismatches (size_t vs. uint64_t) in the stats unit 506 test. 507 - Fix/remove flawed alignment-related overflow tests. 508 - Prevent compiler optimizations that could change backtraces in the 509 prof_accum unit test. 510 511 * 3.5.0 (January 22, 2014) 512 513 This version focuses on refactoring and automated testing, though it also 514 includes some non-trivial heap profiling optimizations not mentioned below. 515 516 New features: 517 - Add the *allocx() API, which is a successor to the experimental *allocm() 518 API. The *allocx() functions are slightly simpler to use because they have 519 fewer parameters, they directly return the results of primary interest, and 520 mallocx()/rallocx() avoid the strict aliasing pitfall that 521 allocm()/rallocm() share with posix_memalign(). Note that *allocm() is 522 slated for removal in the next non-bugfix release. 523 - Add support for LinuxThreads. 524 525 Bug fixes: 526 - Unless heap profiling is enabled, disable floating point code and don't link 527 with libm. This, in combination with e.g. EXTRA_CFLAGS=-mno-sse on x64 528 systems, makes it possible to completely disable floating point register 529 use. Some versions of glibc neglect to save/restore caller-saved floating 530 point registers during dynamic lazy symbol loading, and the symbol loading 531 code uses whatever malloc the application happens to have linked/loaded 532 with, the result being potential floating point register corruption. 533 - Report ENOMEM rather than EINVAL if an OOM occurs during heap profiling 534 backtrace creation in imemalign(). This bug impacted posix_memalign() and 535 aligned_alloc(). 536 - Fix a file descriptor leak in a prof_dump_maps() error path. 537 - Fix prof_dump() to close the dump file descriptor for all relevant error 538 paths. 539 - Fix rallocm() to use the arena specified by the ALLOCM_ARENA(s) flag for 540 allocation, not just deallocation. 541 - Fix a data race for large allocation stats counters. 542 - Fix a potential infinite loop during thread exit. This bug occurred on 543 Solaris, and could affect other platforms with similar pthreads TSD 544 implementations. 545 - Don't junk-fill reallocations unless usable size changes. This fixes a 546 violation of the *allocx()/*allocm() semantics. 547 - Fix growing large reallocation to junk fill new space. 548 - Fix huge deallocation to junk fill when munmap is disabled. 549 - Change the default private namespace prefix from empty to je_, and change 550 --with-private-namespace-prefix so that it prepends an additional prefix 551 rather than replacing je_. This reduces the likelihood of applications 552 which statically link jemalloc experiencing symbol name collisions. 553 - Add missing private namespace mangling (relevant when 554 --with-private-namespace is specified). 555 - Add and use JEMALLOC_INLINE_C so that static inline functions are marked as 556 static even for debug builds. 557 - Add a missing mutex unlock in a malloc_init_hard() error path. In practice 558 this error path is never executed. 559 - Fix numerous bugs in malloc_strotumax() error handling/reporting. These 560 bugs had no impact except for malformed inputs. 561 - Fix numerous bugs in malloc_snprintf(). These bugs were not exercised by 562 existing calls, so they had no impact. 563 564 * 3.4.1 (October 20, 2013) 565 566 Bug fixes: 567 - Fix a race in the "arenas.extend" mallctl that could cause memory corruption 568 of internal data structures and subsequent crashes. 569 - Fix Valgrind integration flaws that caused Valgrind warnings about reads of 570 uninitialized memory in: 571 + arena chunk headers 572 + internal zero-initialized data structures (relevant to tcache and prof 573 code) 574 - Preserve errno during the first allocation. A readlink(2) call during 575 initialization fails unless /etc/malloc.conf exists, so errno was typically 576 set during the first allocation prior to this fix. 577 - Fix compilation warnings reported by gcc 4.8.1. 578 579 * 3.4.0 (June 2, 2013) 580 581 This version is essentially a small bugfix release, but the addition of 582 aarch64 support requires that the minor version be incremented. 583 584 Bug fixes: 585 - Fix race-triggered deadlocks in chunk_record(). These deadlocks were 586 typically triggered by multiple threads concurrently deallocating huge 587 objects. 588 589 New features: 590 - Add support for the aarch64 architecture. 591 592 * 3.3.1 (March 6, 2013) 593 594 This version fixes bugs that are typically encountered only when utilizing 595 custom run-time options. 596 597 Bug fixes: 598 - Fix a locking order bug that could cause deadlock during fork if heap 599 profiling were enabled. 600 - Fix a chunk recycling bug that could cause the allocator to lose track of 601 whether a chunk was zeroed. On FreeBSD, NetBSD, and OS X, it could cause 602 corruption if allocating via sbrk(2) (unlikely unless running with the 603 "dss:primary" option specified). This was completely harmless on Linux 604 unless using mlockall(2) (and unlikely even then, unless the 605 --disable-munmap configure option or the "dss:primary" option was 606 specified). This regression was introduced in 3.1.0 by the 607 mlockall(2)/madvise(2) interaction fix. 608 - Fix TLS-related memory corruption that could occur during thread exit if the 609 thread never allocated memory. Only the quarantine and prof facilities were 610 susceptible. 611 - Fix two quarantine bugs: 612 + Internal reallocation of the quarantined object array leaked the old 613 array. 614 + Reallocation failure for internal reallocation of the quarantined object 615 array (very unlikely) resulted in memory corruption. 616 - Fix Valgrind integration to annotate all internally allocated memory in a 617 way that keeps Valgrind happy about internal data structure access. 618 - Fix building for s390 systems. 619 620 * 3.3.0 (January 23, 2013) 621 622 This version includes a few minor performance improvements in addition to the 623 listed new features and bug fixes. 624 625 New features: 626 - Add clipping support to lg_chunk option processing. 627 - Add the --enable-ivsalloc option. 628 - Add the --without-export option. 629 - Add the --disable-zone-allocator option. 630 631 Bug fixes: 632 - Fix "arenas.extend" mallctl to output the number of arenas. 633 - Fix chunk_recycle() to unconditionally inform Valgrind that returned memory 634 is undefined. 635 - Fix build break on FreeBSD related to alloca.h. 636 637 * 3.2.0 (November 9, 2012) 638 639 In addition to a couple of bug fixes, this version modifies page run 640 allocation and dirty page purging algorithms in order to better control 641 page-level virtual memory fragmentation. 642 643 Incompatible changes: 644 - Change the "opt.lg_dirty_mult" default from 5 to 3 (32:1 to 8:1). 645 646 Bug fixes: 647 - Fix dss/mmap allocation precedence code to use recyclable mmap memory only 648 after primary dss allocation fails. 649 - Fix deadlock in the "arenas.purge" mallctl. This regression was introduced 650 in 3.1.0 by the addition of the "arena.<i>.purge" mallctl. 651 652 * 3.1.0 (October 16, 2012) 653 654 New features: 655 - Auto-detect whether running inside Valgrind, thus removing the need to 656 manually specify MALLOC_CONF=valgrind:true. 657 - Add the "arenas.extend" mallctl, which allows applications to create 658 manually managed arenas. 659 - Add the ALLOCM_ARENA() flag for {,r,d}allocm(). 660 - Add the "opt.dss", "arena.<i>.dss", and "stats.arenas.<i>.dss" mallctls, 661 which provide control over dss/mmap precedence. 662 - Add the "arena.<i>.purge" mallctl, which obsoletes "arenas.purge". 663 - Define LG_QUANTUM for hppa. 664 665 Incompatible changes: 666 - Disable tcache by default if running inside Valgrind, in order to avoid 667 making unallocated objects appear reachable to Valgrind. 668 - Drop const from malloc_usable_size() argument on Linux. 669 670 Bug fixes: 671 - Fix heap profiling crash if sampled object is freed via realloc(p, 0). 672 - Remove const from __*_hook variable declarations, so that glibc can modify 673 them during process forking. 674 - Fix mlockall(2)/madvise(2) interaction. 675 - Fix fork(2)-related deadlocks. 676 - Fix error return value for "thread.tcache.enabled" mallctl. 677 678 * 3.0.0 (May 11, 2012) 679 680 Although this version adds some major new features, the primary focus is on 681 internal code cleanup that facilitates maintainability and portability, most 682 of which is not reflected in the ChangeLog. This is the first release to 683 incorporate substantial contributions from numerous other developers, and the 684 result is a more broadly useful allocator (see the git revision history for 685 contribution details). Note that the license has been unified, thanks to 686 Facebook granting a license under the same terms as the other copyright 687 holders (see COPYING). 688 689 New features: 690 - Implement Valgrind support, redzones, and quarantine. 691 - Add support for additional platforms: 692 + FreeBSD 693 + Mac OS X Lion 694 + MinGW 695 + Windows (no support yet for replacing the system malloc) 696 - Add support for additional architectures: 697 + MIPS 698 + SH4 699 + Tilera 700 - Add support for cross compiling. 701 - Add nallocm(), which rounds a request size up to the nearest size class 702 without actually allocating. 703 - Implement aligned_alloc() (blame C11). 704 - Add the "thread.tcache.enabled" mallctl. 705 - Add the "opt.prof_final" mallctl. 706 - Update pprof (from gperftools 2.0). 707 - Add the --with-mangling option. 708 - Add the --disable-experimental option. 709 - Add the --disable-munmap option, and make it the default on Linux. 710 - Add the --enable-mremap option, which disables use of mremap(2) by default. 711 712 Incompatible changes: 713 - Enable stats by default. 714 - Enable fill by default. 715 - Disable lazy locking by default. 716 - Rename the "tcache.flush" mallctl to "thread.tcache.flush". 717 - Rename the "arenas.pagesize" mallctl to "arenas.page". 718 - Change the "opt.lg_prof_sample" default from 0 to 19 (1 B to 512 KiB). 719 - Change the "opt.prof_accum" default from true to false. 720 721 Removed features: 722 - Remove the swap feature, including the "config.swap", "swap.avail", 723 "swap.prezeroed", "swap.nfds", and "swap.fds" mallctls. 724 - Remove highruns statistics, including the 725 "stats.arenas.<i>.bins.<j>.highruns" and 726 "stats.arenas.<i>.lruns.<j>.highruns" mallctls. 727 - As part of small size class refactoring, remove the "opt.lg_[qc]space_max", 728 "arenas.cacheline", "arenas.subpage", "arenas.[tqcs]space_{min,max}", and 729 "arenas.[tqcs]bins" mallctls. 730 - Remove the "arenas.chunksize" mallctl. 731 - Remove the "opt.lg_prof_tcmax" option. 732 - Remove the "opt.lg_prof_bt_max" option. 733 - Remove the "opt.lg_tcache_gc_sweep" option. 734 - Remove the --disable-tiny option, including the "config.tiny" mallctl. 735 - Remove the --enable-dynamic-page-shift configure option. 736 - Remove the --enable-sysv configure option. 737 738 Bug fixes: 739 - Fix a statistics-related bug in the "thread.arena" mallctl that could cause 740 invalid statistics and crashes. 741 - Work around TLS deallocation via free() on Linux. This bug could cause 742 write-after-free memory corruption. 743 - Fix a potential deadlock that could occur during interval- and 744 growth-triggered heap profile dumps. 745 - Fix large calloc() zeroing bugs due to dropping chunk map unzeroed flags. 746 - Fix chunk_alloc_dss() to stop claiming memory is zeroed. This bug could 747 cause memory corruption and crashes with --enable-dss specified. 748 - Fix fork-related bugs that could cause deadlock in children between fork 749 and exec. 750 - Fix malloc_stats_print() to honor 'b' and 'l' in the opts parameter. 751 - Fix realloc(p, 0) to act like free(p). 752 - Do not enforce minimum alignment in memalign(). 753 - Check for NULL pointer in malloc_usable_size(). 754 - Fix an off-by-one heap profile statistics bug that could be observed in 755 interval- and growth-triggered heap profiles. 756 - Fix the "epoch" mallctl to update cached stats even if the passed in epoch 757 is 0. 758 - Fix bin->runcur management to fix a layout policy bug. This bug did not 759 affect correctness. 760 - Fix a bug in choose_arena_hard() that potentially caused more arenas to be 761 initialized than necessary. 762 - Add missing "opt.lg_tcache_max" mallctl implementation. 763 - Use glibc allocator hooks to make mixed allocator usage less likely. 764 - Fix build issues for --disable-tcache. 765 - Don't mangle pthread_create() when --with-private-namespace is specified. 766 767 * 2.2.5 (November 14, 2011) 768 769 Bug fixes: 770 - Fix huge_ralloc() race when using mremap(2). This is a serious bug that 771 could cause memory corruption and/or crashes. 772 - Fix huge_ralloc() to maintain chunk statistics. 773 - Fix malloc_stats_print(..., "a") output. 774 775 * 2.2.4 (November 5, 2011) 776 777 Bug fixes: 778 - Initialize arenas_tsd before using it. This bug existed for 2.2.[0-3], as 779 well as for --disable-tls builds in earlier releases. 780 - Do not assume a 4 KiB page size in test/rallocm.c. 781 782 * 2.2.3 (August 31, 2011) 783 784 This version fixes numerous bugs related to heap profiling. 785 786 Bug fixes: 787 - Fix a prof-related race condition. This bug could cause memory corruption, 788 but only occurred in non-default configurations (prof_accum:false). 789 - Fix off-by-one backtracing issues (make sure that prof_alloc_prep() is 790 excluded from backtraces). 791 - Fix a prof-related bug in realloc() (only triggered by OOM errors). 792 - Fix prof-related bugs in allocm() and rallocm(). 793 - Fix prof_tdata_cleanup() for --disable-tls builds. 794 - Fix a relative include path, to fix objdir builds. 795 796 * 2.2.2 (July 30, 2011) 797 798 Bug fixes: 799 - Fix a build error for --disable-tcache. 800 - Fix assertions in arena_purge() (for real this time). 801 - Add the --with-private-namespace option. This is a workaround for symbol 802 conflicts that can inadvertently arise when using static libraries. 803 804 * 2.2.1 (March 30, 2011) 805 806 Bug fixes: 807 - Implement atomic operations for x86/x64. This fixes compilation failures 808 for versions of gcc that are still in wide use. 809 - Fix an assertion in arena_purge(). 810 811 * 2.2.0 (March 22, 2011) 812 813 This version incorporates several improvements to algorithms and data 814 structures that tend to reduce fragmentation and increase speed. 815 816 New features: 817 - Add the "stats.cactive" mallctl. 818 - Update pprof (from google-perftools 1.7). 819 - Improve backtracing-related configuration logic, and add the 820 --disable-prof-libgcc option. 821 822 Bug fixes: 823 - Change default symbol visibility from "internal", to "hidden", which 824 decreases the overhead of library-internal function calls. 825 - Fix symbol visibility so that it is also set on OS X. 826 - Fix a build dependency regression caused by the introduction of the .pic.o 827 suffix for PIC object files. 828 - Add missing checks for mutex initialization failures. 829 - Don't use libgcc-based backtracing except on x64, where it is known to work. 830 - Fix deadlocks on OS X that were due to memory allocation in 831 pthread_mutex_lock(). 832 - Heap profiling-specific fixes: 833 + Fix memory corruption due to integer overflow in small region index 834 computation, when using a small enough sample interval that profiling 835 context pointers are stored in small run headers. 836 + Fix a bootstrap ordering bug that only occurred with TLS disabled. 837 + Fix a rallocm() rsize bug. 838 + Fix error detection bugs for aligned memory allocation. 839 840 * 2.1.3 (March 14, 2011) 841 842 Bug fixes: 843 - Fix a cpp logic regression (due to the "thread.{de,}allocatedp" mallctl fix 844 for OS X in 2.1.2). 845 - Fix a "thread.arena" mallctl bug. 846 - Fix a thread cache stats merging bug. 847 848 * 2.1.2 (March 2, 2011) 849 850 Bug fixes: 851 - Fix "thread.{de,}allocatedp" mallctl for OS X. 852 - Add missing jemalloc.a to build system. 853 854 * 2.1.1 (January 31, 2011) 855 856 Bug fixes: 857 - Fix aligned huge reallocation (affected allocm()). 858 - Fix the ALLOCM_LG_ALIGN macro definition. 859 - Fix a heap dumping deadlock. 860 - Fix a "thread.arena" mallctl bug. 861 862 * 2.1.0 (December 3, 2010) 863 864 This version incorporates some optimizations that can't quite be considered 865 bug fixes. 866 867 New features: 868 - Use Linux's mremap(2) for huge object reallocation when possible. 869 - Avoid locking in mallctl*() when possible. 870 - Add the "thread.[de]allocatedp" mallctl's. 871 - Convert the manual page source from roff to DocBook, and generate both roff 872 and HTML manuals. 873 874 Bug fixes: 875 - Fix a crash due to incorrect bootstrap ordering. This only impacted 876 --enable-debug --enable-dss configurations. 877 - Fix a minor statistics bug for mallctl("swap.avail", ...). 878 879 * 2.0.1 (October 29, 2010) 880 881 Bug fixes: 882 - Fix a race condition in heap profiling that could cause undefined behavior 883 if "opt.prof_accum" were disabled. 884 - Add missing mutex unlocks for some OOM error paths in the heap profiling 885 code. 886 - Fix a compilation error for non-C99 builds. 887 888 * 2.0.0 (October 24, 2010) 889 890 This version focuses on the experimental *allocm() API, and on improved 891 run-time configuration/introspection. Nonetheless, numerous performance 892 improvements are also included. 893 894 New features: 895 - Implement the experimental {,r,s,d}allocm() API, which provides a superset 896 of the functionality available via malloc(), calloc(), posix_memalign(), 897 realloc(), malloc_usable_size(), and free(). These functions can be used to 898 allocate/reallocate aligned zeroed memory, ask for optional extra memory 899 during reallocation, prevent object movement during reallocation, etc. 900 - Replace JEMALLOC_OPTIONS/JEMALLOC_PROF_PREFIX with MALLOC_CONF, which is 901 more human-readable, and more flexible. For example: 902 JEMALLOC_OPTIONS=AJP 903 is now: 904 MALLOC_CONF=abort:true,fill:true,stats_print:true 905 - Port to Apple OS X. Sponsored by Mozilla. 906 - Make it possible for the application to control thread-->arena mappings via 907 the "thread.arena" mallctl. 908 - Add compile-time support for all TLS-related functionality via pthreads TSD. 909 This is mainly of interest for OS X, which does not support TLS, but has a 910 TSD implementation with similar performance. 911 - Override memalign() and valloc() if they are provided by the system. 912 - Add the "arenas.purge" mallctl, which can be used to synchronously purge all 913 dirty unused pages. 914 - Make cumulative heap profiling data optional, so that it is possible to 915 limit the amount of memory consumed by heap profiling data structures. 916 - Add per thread allocation counters that can be accessed via the 917 "thread.allocated" and "thread.deallocated" mallctls. 918 919 Incompatible changes: 920 - Remove JEMALLOC_OPTIONS and malloc_options (see MALLOC_CONF above). 921 - Increase default backtrace depth from 4 to 128 for heap profiling. 922 - Disable interval-based profile dumps by default. 923 924 Bug fixes: 925 - Remove bad assertions in fork handler functions. These assertions could 926 cause aborts for some combinations of configure settings. 927 - Fix strerror_r() usage to deal with non-standard semantics in GNU libc. 928 - Fix leak context reporting. This bug tended to cause the number of contexts 929 to be underreported (though the reported number of objects and bytes were 930 correct). 931 - Fix a realloc() bug for large in-place growing reallocation. This bug could 932 cause memory corruption, but it was hard to trigger. 933 - Fix an allocation bug for small allocations that could be triggered if 934 multiple threads raced to create a new run of backing pages. 935 - Enhance the heap profiler to trigger samples based on usable size, rather 936 than request size. 937 - Fix a heap profiling bug due to sometimes losing track of requested object 938 size for sampled objects. 939 940 * 1.0.3 (August 12, 2010) 941 942 Bug fixes: 943 - Fix the libunwind-based implementation of stack backtracing (used for heap 944 profiling). This bug could cause zero-length backtraces to be reported. 945 - Add a missing mutex unlock in library initialization code. If multiple 946 threads raced to initialize malloc, some of them could end up permanently 947 blocked. 948 949 * 1.0.2 (May 11, 2010) 950 951 Bug fixes: 952 - Fix junk filling of large objects, which could cause memory corruption. 953 - Add MAP_NORESERVE support for chunk mapping, because otherwise virtual 954 memory limits could cause swap file configuration to fail. Contributed by 955 Jordan DeLong. 956 957 * 1.0.1 (April 14, 2010) 958 959 Bug fixes: 960 - Fix compilation when --enable-fill is specified. 961 - Fix threads-related profiling bugs that affected accuracy and caused memory 962 to be leaked during thread exit. 963 - Fix dirty page purging race conditions that could cause crashes. 964 - Fix crash in tcache flushing code during thread destruction. 965 966 * 1.0.0 (April 11, 2010) 967 968 This release focuses on speed and run-time introspection. Numerous 969 algorithmic improvements make this release substantially faster than its 970 predecessors. 971 972 New features: 973 - Implement autoconf-based configuration system. 974 - Add mallctl*(), for the purposes of introspection and run-time 975 configuration. 976 - Make it possible for the application to manually flush a thread's cache, via 977 the "tcache.flush" mallctl. 978 - Base maximum dirty page count on proportion of active memory. 979 - Compute various additional run-time statistics, including per size class 980 statistics for large objects. 981 - Expose malloc_stats_print(), which can be called repeatedly by the 982 application. 983 - Simplify the malloc_message() signature to only take one string argument, 984 and incorporate an opaque data pointer argument for use by the application 985 in combination with malloc_stats_print(). 986 - Add support for allocation backed by one or more swap files, and allow the 987 application to disable over-commit if swap files are in use. 988 - Implement allocation profiling and leak checking. 989 990 Removed features: 991 - Remove the dynamic arena rebalancing code, since thread-specific caching 992 reduces its utility. 993 994 Bug fixes: 995 - Modify chunk allocation to work when address space layout randomization 996 (ASLR) is in use. 997 - Fix thread cleanup bugs related to TLS destruction. 998 - Handle 0-size allocation requests in posix_memalign(). 999 - Fix a chunk leak. The leaked chunks were never touched, so this impacted 1000 virtual memory usage, but not physical memory usage. 1001 1002 * linux_2008082[78]a (August 27/28, 2008) 1003 1004 These snapshot releases are the simple result of incorporating Linux-specific 1005 support into the FreeBSD malloc sources. 1006 1007 -------------------------------------------------------------------------------- 1008 vim:filetype=text:textwidth=80 1009
