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diff --git a/deps/jemalloc/ChangeLog b/deps/jemalloc/ChangeLog index e3b0a5190..29a00fb78 100644 --- a/deps/jemalloc/ChangeLog +++ b/deps/jemalloc/ChangeLog @@ -4,6 +4,600 @@ brevity. Much more detail can be found in the git revision history: https://github.com/jemalloc/jemalloc +* 5.1.0 (May 4th, 2018) + + This release is primarily about fine-tuning, ranging from several new features + to numerous notable performance and portability enhancements. The release and + prior dev versions have been running in multiple large scale applications for + months, and the cumulative improvements are substantial in many cases. + + Given the long and successful production runs, this release is likely a good + candidate for applications to upgrade, from both jemalloc 5.0 and before. For + performance-critical applications, the newly added TUNING.md provides + guidelines on jemalloc tuning. + + New features: + - Implement transparent huge page support for internal metadata. (@interwq) + - Add opt.thp to allow enabling / disabling transparent huge pages for all + mappings. (@interwq) + - Add maximum background thread count option. (@djwatson) + - Allow prof_active to control opt.lg_prof_interval and prof.gdump. + (@interwq) + - Allow arena index lookup based on allocation addresses via mallctl. + (@lionkov) + - Allow disabling initial-exec TLS model. (@davidtgoldblatt, @KenMacD) + - Add opt.lg_extent_max_active_fit to set the max ratio between the size of + the active extent selected (to split off from) and the size of the requested + allocation. (@interwq, @davidtgoldblatt) + - Add retain_grow_limit to set the max size when growing virtual address + space. (@interwq) + - Add mallctl interfaces: + + arena.<i>.retain_grow_limit (@interwq) + + arenas.lookup (@lionkov) + + max_background_threads (@djwatson) + + opt.lg_extent_max_active_fit (@interwq) + + opt.max_background_threads (@djwatson) + + opt.metadata_thp (@interwq) + + opt.thp (@interwq) + + stats.metadata_thp (@interwq) + + Portability improvements: + - Support GNU/kFreeBSD configuration. (@paravoid) + - Support m68k, nios2 and SH3 architectures. (@paravoid) + - Fall back to FD_CLOEXEC when O_CLOEXEC is unavailable. (@zonyitoo) + - Fix symbol listing for cross-compiling. (@tamird) + - Fix high bits computation on ARM. (@davidtgoldblatt, @paravoid) + - Disable the CPU_SPINWAIT macro for Power. (@davidtgoldblatt, @marxin) + - Fix MSVC 2015 & 2017 builds. (@rustyx) + - Improve RISC-V support. (@EdSchouten) + - Set name mangling script in strict mode. (@nicolov) + - Avoid MADV_HUGEPAGE on ARM. (@marxin) + - Modify configure to determine return value of strerror_r. + (@davidtgoldblatt, @cferris1000) + - Make sure CXXFLAGS is tested with CPP compiler. (@nehaljwani) + - Fix 32-bit build on MSVC. (@rustyx) + - Fix external symbol on MSVC. (@maksqwe) + - Avoid a printf format specifier warning. (@jasone) + - Add configure option --disable-initial-exec-tls which can allow jemalloc to + be dynamically loaded after program startup. (@davidtgoldblatt, @KenMacD) + - AArch64: Add ILP32 support. (@cmuellner) + - Add --with-lg-vaddr configure option to support cross compiling. + (@cmuellner, @davidtgoldblatt) + + Optimizations and refactors: + - Improve active extent fit with extent_max_active_fit. This considerably + reduces fragmentation over time and improves virtual memory and metadata + usage. (@davidtgoldblatt, @interwq) + - Eagerly coalesce large extents to reduce fragmentation. (@interwq) + - sdallocx: only read size info when page aligned (i.e. possibly sampled), + which speeds up the sized deallocation path significantly. (@interwq) + - Avoid attempting new mappings for in place expansion with retain, since + it rarely succeeds in practice and causes high overhead. (@interwq) + - Refactor OOM handling in newImpl. (@wqfish) + - Add internal fine-grained logging functionality for debugging use. + (@davidtgoldblatt) + - Refactor arena / tcache interactions. (@davidtgoldblatt) + - Refactor extent management with dumpable flag. (@davidtgoldblatt) + - Add runtime detection of lazy purging. (@interwq) + - Use pairing heap instead of red-black tree for extents_avail. (@djwatson) + - Use sysctl on startup in FreeBSD. (@trasz) + - Use thread local prng state instead of atomic. (@djwatson) + - Make decay to always purge one more extent than before, because in + practice large extents are usually the ones that cross the decay threshold. + Purging the additional extent helps save memory as well as reduce VM + fragmentation. (@interwq) + - Fast division by dynamic values. (@davidtgoldblatt) + - Improve the fit for aligned allocation. (@interwq, @edwinsmith) + - Refactor extent_t bitpacking. (@rkmisra) + - Optimize the generated assembly for ticker operations. (@davidtgoldblatt) + - Convert stats printing to use a structured text emitter. (@davidtgoldblatt) + - Remove preserve_lru feature for extents management. (@djwatson) + - Consolidate two memory loads into one on the fast deallocation path. + (@davidtgoldblatt, @interwq) + + Bug fixes (most of the issues are only relevant to jemalloc 5.0): + - Fix deadlock with multithreaded fork in OS X. (@davidtgoldblatt) + - Validate returned file descriptor before use. (@zonyitoo) + - Fix a few background thread initialization and shutdown issues. (@interwq) + - Fix an extent coalesce + decay race by taking both coalescing extents off + the LRU list. (@interwq) + - Fix potentially unbound increase during decay, caused by one thread keep + stashing memory to purge while other threads generating new pages. The + number of pages to purge is checked to prevent this. (@interwq) + - Fix a FreeBSD bootstrap assertion. (@strejda, @interwq) + - Handle 32 bit mutex counters. (@rkmisra) + - Fix a indexing bug when creating background threads. (@davidtgoldblatt, + @binliu19) + - Fix arguments passed to extent_init. (@yuleniwo, @interwq) + - Fix addresses used for ordering mutexes. (@rkmisra) + - Fix abort_conf processing during bootstrap. (@interwq) + - Fix include path order for out-of-tree builds. (@cmuellner) + + Incompatible changes: + - Remove --disable-thp. (@interwq) + - Remove mallctl interfaces: + + config.thp (@interwq) + + Documentation: + - Add TUNING.md. (@interwq, @davidtgoldblatt, @djwatson) + +* 5.0.1 (July 1, 2017) + + This bugfix release fixes several issues, most of which are obscure enough + that typical applications are not impacted. + + Bug fixes: + - Update decay->nunpurged before purging, in order to avoid potential update + races and subsequent incorrect purging volume. (@interwq) + - Only abort on dlsym(3) error if the failure impacts an enabled feature (lazy + locking and/or background threads). This mitigates an initialization + failure bug for which we still do not have a clear reproduction test case. + (@interwq) + - Modify tsd management so that it neither crashes nor leaks if a thread's + only allocation activity is to call free() after TLS destructors have been + executed. This behavior was observed when operating with GNU libc, and is + unlikely to be an issue with other libc implementations. (@interwq) + - Mask signals during background thread creation. This prevents signals from + being inadvertently delivered to background threads. (@jasone, + @davidtgoldblatt, @interwq) + - Avoid inactivity checks within background threads, in order to prevent + recursive mutex acquisition. (@interwq) + - Fix extent_grow_retained() to use the specified hooks when the + arena.<i>.extent_hooks mallctl is used to override the default hooks. + (@interwq) + - Add missing reentrancy support for custom extent hooks which allocate. + (@interwq) + - Post-fork(2), re-initialize the list of tcaches associated with each arena + to contain no tcaches except the forking thread's. (@interwq) + - Add missing post-fork(2) mutex reinitialization for extent_grow_mtx. This + fixes potential deadlocks after fork(2). (@interwq) + - Enforce minimum autoconf version (currently 2.68), since 2.63 is known to + generate corrupt configure scripts. (@jasone) + - Ensure that the configured page size (--with-lg-page) is no larger than the + configured huge page size (--with-lg-hugepage). (@jasone) + +* 5.0.0 (June 13, 2017) + + Unlike all previous jemalloc releases, this release does not use naturally + aligned "chunks" for virtual memory management, and instead uses page-aligned + "extents". This change has few externally visible effects, but the internal + impacts are... extensive. Many other internal changes combine to make this + the most cohesively designed version of jemalloc so far, with ample + opportunity for further enhancements. + + Continuous integration is now an integral aspect of development thanks to the + efforts of @davidtgoldblatt, and the dev branch tends to remain reasonably + stable on the tested platforms (Linux, FreeBSD, macOS, and Windows). As a + side effect the official release frequency may decrease over time. + + New features: + - Implement optional per-CPU arena support; threads choose which arena to use + based on current CPU rather than on fixed thread-->arena associations. + (@interwq) + - Implement two-phase decay of unused dirty pages. Pages transition from + dirty-->muzzy-->clean, where the first phase transition relies on + madvise(... MADV_FREE) semantics, and the second phase transition discards + pages such that they are replaced with demand-zeroed pages on next access. + (@jasone) + - Increase decay time resolution from seconds to milliseconds. (@jasone) + - Implement opt-in per CPU background threads, and use them for asynchronous + decay-driven unused dirty page purging. (@interwq) + - Add mutex profiling, which collects a variety of statistics useful for + diagnosing overhead/contention issues. (@interwq) + - Add C++ new/delete operator bindings. (@djwatson) + - Support manually created arena destruction, such that all data and metadata + are discarded. Add MALLCTL_ARENAS_DESTROYED for accessing merged stats + associated with destroyed arenas. (@jasone) + - Add MALLCTL_ARENAS_ALL as a fixed index for use in accessing + merged/destroyed arena statistics via mallctl. (@jasone) + - Add opt.abort_conf to optionally abort if invalid configuration options are + detected during initialization. (@interwq) + - Add opt.stats_print_opts, so that e.g. JSON output can be selected for the + stats dumped during exit if opt.stats_print is true. (@jasone) + - Add --with-version=VERSION for use when embedding jemalloc into another + project's git repository. (@jasone) + - Add --disable-thp to support cross compiling. (@jasone) + - Add --with-lg-hugepage to support cross compiling. (@jasone) + - Add mallctl interfaces (various authors): + + background_thread + + opt.abort_conf + + opt.retain + + opt.percpu_arena + + opt.background_thread + + opt.{dirty,muzzy}_decay_ms + + opt.stats_print_opts + + arena.<i>.initialized + + arena.<i>.destroy + + arena.<i>.{dirty,muzzy}_decay_ms + + arena.<i>.extent_hooks + + arenas.{dirty,muzzy}_decay_ms + + arenas.bin.<i>.slab_size + + arenas.nlextents + + arenas.lextent.<i>.size + + arenas.create + + stats.background_thread.{num_threads,num_runs,run_interval} + + stats.mutexes.{ctl,background_thread,prof,reset}. + {num_ops,num_spin_acq,num_wait,max_wait_time,total_wait_time,max_num_thds, + num_owner_switch} + + stats.arenas.<i>.{dirty,muzzy}_decay_ms + + stats.arenas.<i>.uptime + + stats.arenas.<i>.{pmuzzy,base,internal,resident} + + stats.arenas.<i>.{dirty,muzzy}_{npurge,nmadvise,purged} + + stats.arenas.<i>.bins.<j>.{nslabs,reslabs,curslabs} + + stats.arenas.<i>.bins.<j>.mutex. + {num_ops,num_spin_acq,num_wait,max_wait_time,total_wait_time,max_num_thds, + num_owner_switch} + + stats.arenas.<i>.lextents.<j>.{nmalloc,ndalloc,nrequests,curlextents} + + stats.arenas.i.mutexes.{large,extent_avail,extents_dirty,extents_muzzy, + extents_retained,decay_dirty,decay_muzzy,base,tcache_list}. + {num_ops,num_spin_acq,num_wait,max_wait_time,total_wait_time,max_num_thds, + num_owner_switch} + + Portability improvements: + - Improve reentrant allocation support, such that deadlock is less likely if + e.g. a system library call in turn allocates memory. (@davidtgoldblatt, + @interwq) + - Support static linking of jemalloc with glibc. (@djwatson) + + Optimizations and refactors: + - Organize virtual memory as "extents" of virtual memory pages, rather than as + naturally aligned "chunks", and store all metadata in arbitrarily distant + locations. This reduces virtual memory external fragmentation, and will + interact better with huge pages (not yet explicitly supported). (@jasone) + - Fold large and huge size classes together; only small and large size classes + remain. (@jasone) + - Unify the allocation paths, and merge most fast-path branching decisions. + (@davidtgoldblatt, @interwq) + - Embed per thread automatic tcache into thread-specific data, which reduces + conditional branches and dereferences. Also reorganize tcache to increase + fast-path data locality. (@interwq) + - Rewrite atomics to closely model the C11 API, convert various + synchronization from mutex-based to atomic, and use the explicit memory + ordering control to resolve various hypothetical races without increasing + synchronization overhead. (@davidtgoldblatt) + - Extensively optimize rtree via various methods: + + Add multiple layers of rtree lookup caching, since rtree lookups are now + part of fast-path deallocation. (@interwq) + + Determine rtree layout at compile time. (@jasone) + + Make the tree shallower for common configurations. (@jasone) + + Embed the root node in the top-level rtree data structure, thus avoiding + one level of indirection. (@jasone) + + Further specialize leaf elements as compared to internal node elements, + and directly embed extent metadata needed for fast-path deallocation. + (@jasone) + + Ignore leading always-zero address bits (architecture-specific). + (@jasone) + - Reorganize headers (ongoing work) to make them hermetic, and disentangle + various module dependencies. (@davidtgoldblatt) + - Convert various internal data structures such as size class metadata from + boot-time-initialized to compile-time-initialized. Propagate resulting data + structure simplifications, such as making arena metadata fixed-size. + (@jasone) + - Simplify size class lookups when constrained to size classes that are + multiples of the page size. This speeds lookups, but the primary benefit is + complexity reduction in code that was the source of numerous regressions. + (@jasone) + - Lock individual extents when possible for localized extent operations, + rather than relying on a top-level arena lock. (@davidtgoldblatt, @jasone) + - Use first fit layout policy instead of best fit, in order to improve + packing. (@jasone) + - If munmap(2) is not in use, use an exponential series to grow each arena's + virtual memory, so that the number of disjoint virtual memory mappings + remains low. (@jasone) + - Implement per arena base allocators, so that arenas never share any virtual + memory pages. (@jasone) + - Automatically generate private symbol name mangling macros. (@jasone) + + Incompatible changes: + - Replace chunk hooks with an expanded/normalized set of extent hooks. + (@jasone) + - Remove ratio-based purging. (@jasone) + - Remove --disable-tcache. (@jasone) + - Remove --disable-tls. (@jasone) + - Remove --enable-ivsalloc. (@jasone) + - Remove --with-lg-size-class-group. (@jasone) + - Remove --with-lg-tiny-min. (@jasone) + - Remove --disable-cc-silence. (@jasone) + - Remove --enable-code-coverage. (@jasone) + - Remove --disable-munmap (replaced by opt.retain). (@jasone) + - Remove Valgrind support. (@jasone) + - Remove quarantine support. (@jasone) + - Remove redzone support. (@jasone) + - Remove mallctl interfaces (various authors): + + config.munmap + + config.tcache + + config.tls + + config.valgrind + + opt.lg_chunk + + opt.purge + + opt.lg_dirty_mult + + opt.decay_time + + opt.quarantine + + opt.redzone + + opt.thp + + arena.<i>.lg_dirty_mult + + arena.<i>.decay_time + + arena.<i>.chunk_hooks + + arenas.initialized + + arenas.lg_dirty_mult + + arenas.decay_time + + arenas.bin.<i>.run_size + + arenas.nlruns + + arenas.lrun.<i>.size + + arenas.nhchunks + + arenas.hchunk.<i>.size + + arenas.extend + + stats.cactive + + stats.arenas.<i>.lg_dirty_mult + + stats.arenas.<i>.decay_time + + stats.arenas.<i>.metadata.{mapped,allocated} + + stats.arenas.<i>.{npurge,nmadvise,purged} + + stats.arenas.<i>.huge.{allocated,nmalloc,ndalloc,nrequests} + + stats.arenas.<i>.bins.<j>.{nruns,reruns,curruns} + + stats.arenas.<i>.lruns.<j>.{nmalloc,ndalloc,nrequests,curruns} + + stats.arenas.<i>.hchunks.<j>.{nmalloc,ndalloc,nrequests,curhchunks} + + Bug fixes: + - Improve interval-based profile dump triggering to dump only one profile when + a single allocation's size exceeds the interval. (@jasone) + - Use prefixed function names (as controlled by --with-jemalloc-prefix) when + pruning backtrace frames in jeprof. (@jasone) + +* 4.5.0 (February 28, 2017) + + This is the first release to benefit from much broader continuous integration + testing, thanks to @davidtgoldblatt. Had we had this testing infrastructure + in place for prior releases, it would have caught all of the most serious + regressions fixed by this release. + + New features: + - Add --disable-thp and the opt.thp mallctl to provide opt-out mechanisms for + transparent huge page integration. (@jasone) + - Update zone allocator integration to work with macOS 10.12. (@glandium) + - Restructure *CFLAGS configuration, so that CFLAGS behaves typically, and + EXTRA_CFLAGS provides a way to specify e.g. -Werror during building, but not + during configuration. (@jasone, @ronawho) + + Bug fixes: + - Fix DSS (sbrk(2)-based) allocation. This regression was first released in + 4.3.0. (@jasone) + - Handle race in per size class utilization computation. This functionality + was first released in 4.0.0. (@interwq) + - Fix lock order reversal during gdump. (@jasone) + - Fix/refactor tcache synchronization. This regression was first released in + 4.0.0. (@jasone) + - Fix various JSON-formatted malloc_stats_print() bugs. This functionality + was first released in 4.3.0. (@jasone) + - Fix huge-aligned allocation. This regression was first released in 4.4.0. + (@jasone) + - When transparent huge page integration is enabled, detect what state pages + start in according to the kernel's current operating mode, and only convert + arena chunks to non-huge during purging if that is not their initial state. + This functionality was first released in 4.4.0. (@jasone) + - Fix lg_chunk clamping for the --enable-cache-oblivious --disable-fill case. + This regression was first released in 4.0.0. (@jasone, @428desmo) + - Properly detect sparc64 when building for Linux. (@glaubitz) + +* 4.4.0 (December 3, 2016) + + New features: + - Add configure support for *-*-linux-android. (@cferris1000, @jasone) + - Add the --disable-syscall configure option, for use on systems that place + security-motivated limitations on syscall(2). (@jasone) + - Add support for Debian GNU/kFreeBSD. (@thesam) + + Optimizations: + - Add extent serial numbers and use them where appropriate as a sort key that + is higher priority than address, so that the allocation policy prefers older + extents. This tends to improve locality (decrease fragmentation) when + memory grows downward. (@jasone) + - Refactor madvise(2) configuration so that MADV_FREE is detected and utilized + on Linux 4.5 and newer. (@jasone) + - Mark partially purged arena chunks as non-huge-page. This improves + interaction with Linux's transparent huge page functionality. (@jasone) + + Bug fixes: + - Fix size class computations for edge conditions involving extremely large + allocations. This regression was first released in 4.0.0. (@jasone, + @ingvarha) + - Remove overly restrictive assertions related to the cactive statistic. This + regression was first released in 4.1.0. (@jasone) + - Implement a more reliable detection scheme for os_unfair_lock on macOS. + (@jszakmeister) + +* 4.3.1 (November 7, 2016) + + Bug fixes: + - Fix a severe virtual memory leak. This regression was first released in + 4.3.0. (@interwq, @jasone) + - Refactor atomic and prng APIs to restore support for 32-bit platforms that + use pre-C11 toolchains, e.g. FreeBSD's mips. (@jasone) + +* 4.3.0 (November 4, 2016) + + This is the first release that passes the test suite for multiple Windows + configurations, thanks in large part to @glandium setting up continuous + integration via AppVeyor (and Travis CI for Linux and OS X). + + New features: + - Add "J" (JSON) support to malloc_stats_print(). (@jasone) + - Add Cray compiler support. (@ronawho) + + Optimizations: + - Add/use adaptive spinning for bootstrapping and radix tree node + initialization. (@jasone) + + Bug fixes: + - Fix large allocation to search starting in the optimal size class heap, + which can substantially reduce virtual memory churn and fragmentation. This + regression was first released in 4.0.0. (@mjp41, @jasone) + - Fix stats.arenas.<i>.nthreads accounting. (@interwq) + - Fix and simplify decay-based purging. (@jasone) + - Make DSS (sbrk(2)-related) operations lockless, which resolves potential + deadlocks during thread exit. (@jasone) + - Fix over-sized allocation of radix tree leaf nodes. (@mjp41, @ogaun, + @jasone) + - Fix over-sized allocation of arena_t (plus associated stats) data + structures. (@jasone, @interwq) + - Fix EXTRA_CFLAGS to not affect configuration. (@jasone) + - Fix a Valgrind integration bug. (@ronawho) + - Disallow 0x5a junk filling when running in Valgrind. (@jasone) + - Fix a file descriptor leak on Linux. This regression was first released in + 4.2.0. (@vsarunas, @jasone) + - Fix static linking of jemalloc with glibc. (@djwatson) + - Use syscall(2) rather than {open,read,close}(2) during boot on Linux. This + works around other libraries' system call wrappers performing reentrant + allocation. (@kspinka, @Whissi, @jasone) + - Fix OS X default zone replacement to work with OS X 10.12. (@glandium, + @jasone) + - Fix cached memory management to avoid needless commit/decommit operations + during purging, which resolves permanent virtual memory map fragmentation + issues on Windows. (@mjp41, @jasone) + - Fix TSD fetches to avoid (recursive) allocation. This is relevant to + non-TLS and Windows configurations. (@jasone) + - Fix malloc_conf overriding to work on Windows. (@jasone) + - Forcibly disable lazy-lock on Windows (was forcibly *enabled*). (@jasone) + +* 4.2.1 (June 8, 2016) + + Bug fixes: + - Fix bootstrapping issues for configurations that require allocation during + tsd initialization (e.g. --disable-tls). (@cferris1000, @jasone) + - Fix gettimeofday() version of nstime_update(). (@ronawho) + - Fix Valgrind regressions in calloc() and chunk_alloc_wrapper(). (@ronawho) + - Fix potential VM map fragmentation regression. (@jasone) + - Fix opt_zero-triggered in-place huge reallocation zeroing. (@jasone) + - Fix heap profiling context leaks in reallocation edge cases. (@jasone) + +* 4.2.0 (May 12, 2016) + + New features: + - Add the arena.<i>.reset mallctl, which makes it possible to discard all of + an arena's allocations in a single operation. (@jasone) + - Add the stats.retained and stats.arenas.<i>.retained statistics. (@jasone) + - Add the --with-version configure option. (@jasone) + - Support --with-lg-page values larger than actual page size. (@jasone) + + Optimizations: + - Use pairing heaps rather than red-black trees for various hot data + structures. (@djwatson, @jasone) + - Streamline fast paths of rtree operations. (@jasone) + - Optimize the fast paths of calloc() and [m,d,sd]allocx(). (@jasone) + - Decommit unused virtual memory if the OS does not overcommit. (@jasone) + - Specify MAP_NORESERVE on Linux if [heuristic] overcommit is active, in order + to avoid unfortunate interactions during fork(2). (@jasone) + + Bug fixes: + - Fix chunk accounting related to triggering gdump profiles. (@jasone) + - Link against librt for clock_gettime(2) if glibc < 2.17. (@jasone) + - Scale leak report summary according to sampling probability. (@jasone) + +* 4.1.1 (May 3, 2016) + + This bugfix release resolves a variety of mostly minor issues, though the + bitmap fix is critical for 64-bit Windows. + + Bug fixes: + - Fix the linear scan version of bitmap_sfu() to shift by the proper amount + even when sizeof(long) is not the same as sizeof(void *), as on 64-bit + Windows. (@jasone) + - Fix hashing functions to avoid unaligned memory accesses (and resulting + crashes). This is relevant at least to some ARM-based platforms. + (@rkmisra) + - Fix fork()-related lock rank ordering reversals. These reversals were + unlikely to cause deadlocks in practice except when heap profiling was + enabled and active. (@jasone) + - Fix various chunk leaks in OOM code paths. (@jasone) + - Fix malloc_stats_print() to print opt.narenas correctly. (@jasone) + - Fix MSVC-specific build/test issues. (@rustyx, @yuslepukhin) + - Fix a variety of test failures that were due to test fragility rather than + core bugs. (@jasone) + +* 4.1.0 (February 28, 2016) + + This release is primarily about optimizations, but it also incorporates a lot + of portability-motivated refactoring and enhancements. Many people worked on + this release, to an extent that even with the omission here of minor changes + (see git revision history), and of the people who reported and diagnosed + issues, so much of the work was contributed that starting with this release, + changes are annotated with author credits to help reflect the collaborative + effort involved. + + New features: + - Implement decay-based unused dirty page purging, a major optimization with + mallctl API impact. This is an alternative to the existing ratio-based + unused dirty page purging, and is intended to eventually become the sole + purging mechanism. New mallctls: + + opt.purge + + opt.decay_time + + arena.<i>.decay + + arena.<i>.decay_time + + arenas.decay_time + + stats.arenas.<i>.decay_time + (@jasone, @cevans87) + - Add --with-malloc-conf, which makes it possible to embed a default + options string during configuration. This was motivated by the desire to + specify --with-malloc-conf=purge:decay , since the default must remain + purge:ratio until the 5.0.0 release. (@jasone) + - Add MS Visual Studio 2015 support. (@rustyx, @yuslepukhin) + - Make *allocx() size class overflow behavior defined. The maximum + size class is now less than PTRDIFF_MAX to protect applications against + numerical overflow, and all allocation functions are guaranteed to indicate + errors rather than potentially crashing if the request size exceeds the + maximum size class. (@jasone) + - jeprof: + + Add raw heap profile support. (@jasone) + + Add --retain and --exclude for backtrace symbol filtering. (@jasone) + + Optimizations: + - Optimize the fast path to combine various bootstrapping and configuration + checks and execute more streamlined code in the common case. (@interwq) + - Use linear scan for small bitmaps (used for small object tracking). In + addition to speeding up bitmap operations on 64-bit systems, this reduces + allocator metadata overhead by approximately 0.2%. (@djwatson) + - Separate arena_avail trees, which substantially speeds up run tree + operations. (@djwatson) + - Use memoization (boot-time-computed table) for run quantization. Separate + arena_avail trees reduced the importance of this optimization. (@jasone) + - Attempt mmap-based in-place huge reallocation. This can dramatically speed + up incremental huge reallocation. (@jasone) + + Incompatible changes: + - Make opt.narenas unsigned rather than size_t. (@jasone) + + Bug fixes: + - Fix stats.cactive accounting regression. (@rustyx, @jasone) + - Handle unaligned keys in hash(). This caused problems for some ARM systems. + (@jasone, @cferris1000) + - Refactor arenas array. In addition to fixing a fork-related deadlock, this + makes arena lookups faster and simpler. (@jasone) + - Move retained memory allocation out of the default chunk allocation + function, to a location that gets executed even if the application installs + a custom chunk allocation function. This resolves a virtual memory leak. + (@buchgr) + - Fix a potential tsd cleanup leak. (@cferris1000, @jasone) + - Fix run quantization. In practice this bug had no impact unless + applications requested memory with alignment exceeding one page. + (@jasone, @djwatson) + - Fix LinuxThreads-specific bootstrapping deadlock. (Cosmin Paraschiv) + - jeprof: + + Don't discard curl options if timeout is not defined. (@djwatson) + + Detect failed profile fetches. (@djwatson) + - Fix stats.arenas.<i>.{dss,lg_dirty_mult,decay_time,pactive,pdirty} for + --disable-stats case. (@jasone) + +* 4.0.4 (October 24, 2015) + + This bugfix release fixes another xallocx() regression. No other regressions + have come to light in over a month, so this is likely a good starting point + for people who prefer to wait for "dot one" releases with all the major issues + shaken out. + + Bug fixes: + - Fix xallocx(..., MALLOCX_ZERO to zero the last full trailing page of large + allocations that have been randomly assigned an offset of 0 when + --enable-cache-oblivious configure option is enabled. + * 4.0.3 (September 24, 2015) This bugfix release continues the trend of xallocx() and heap profiling fixes. @@ -38,7 +632,7 @@ brevity. Much more detail can be found in the git revision history: these fixes, xallocx() now tries harder to partially fulfill requests for optional extra space. Note that a couple of minor heap profiling optimizations are included, but these are better thought of as performance - fixes that were integral to disovering most of the other bugs. + fixes that were integral to discovering most of the other bugs. Optimizations: - Avoid a chunk metadata read in arena_prof_tctx_set(), since it is in the |