Crate jemalloc_sys

Expand description

Rust bindings to the jemalloc C library.

jemalloc is a general purpose memory allocation, its documentation can be found here:

API documentation
Wiki (design documents, presentations, profiling, debugging, tuning, …)

jemalloc exposes both a standard and a non-standard API.

§Standard API

The standard API includes: the malloc, calloc, realloc, and free, which conform to to ISO/IEC 9899:1990 (“ISO C90”), posix_memalign which conforms to conforms to POSIX.1-2016, and aligned_alloc.

Note that these standard leave some details as implementation defined. This docs document this behavior for jemalloc, but keep in mind that other standard-conforming implementations of these functions in other allocators might behave slightly different.

§Non-Standard API

The non-standard API includes: mallocx, rallocx, xallocx, sallocx, dallocx, sdallocx, and nallocx. These functions all have a flags argument that can be used to specify options. Use bitwise or | to specify one or more of the following: MALLOCX_LG_ALIGN, MALLOCX_ALIGN, MALLOCX_ZERO, MALLOCX_TCACHE, MALLOCX_TCACHE_NONE, and MALLOCX_ARENA.

§Environment variables

The MALLOC_CONF environment variable affects the execution of the allocation functions.

For the documentation of the MALLCTL namespace visit the jemalloc documenation.

Structs§

extent_hooks_s: Extent lifetime management functions.

Constants§

MALLOCX_TCACHE_NONE: Do not use a thread-specific cache (tcache).
MALLOCX_ZERO: Initialize newly allocated memory to contain zero bytes.

Statics§

NO_BG_THREAD_TARGETS: jemalloc’s background_thread support is known not to work on these targets:
NO_UNPREFIXED_MALLOC_TARGETS: targets that don’t support unprefixed malloc
UNSUPPORTED_TARGETS: jemalloc is known not to work on these targets:
UNTESTED_TARGETS: jemalloc-sys is not tested on these targets in CI:
malloc_conf^⚠: Compile-time string of configuration options.
malloc_message^⚠: Allows overriding the function which emits the text strings forming the errors and warnings if for some reason the STDERR_FILENO file descriptor is not suitable for this.

Functions§

MALLOCX_ALIGN: Align the memory allocation to start at an address that is a multiple of align, where a is a power of two.
MALLOCX_ARENA: Use the arena specified by the index a.
MALLOCX_LG_ALIGN: Align the memory allocation to start at an address that is a multiple of 1 << la.
MALLOCX_TCACHE: Use the thread-specific cache (tcache) specified by the identifier tc.
aligned_alloc^⚠: Allocates size bytes of memory at an address which is a multiple of alignment.
calloc^⚠: Allocates zero-initialized space for an array of number objects, each of whose size is size.
dallocx^⚠: Deallocates previously-allocated memory region referenced by ptr.
free^⚠: Deallocates previously-allocated memory region referenced by ptr.
mallctl^⚠: General interface for introspecting the memory allocator, as well as setting modifiable parameters and triggering actions.
mallctlbymib^⚠: Like mallctl but taking a mib as input instead of a name.
mallctlnametomib^⚠: Translates a name to a “Management Information Base” (MIB) that can be passed repeatedly to mallctlbymib.
malloc^⚠: Allocates size bytes of uninitialized memory.
malloc_stats_print^⚠: Writes summary statistics via the write_cb callback function pointer and cbopaque data passed to write_cb, or malloc_message if write_cb is null.
malloc_usable_size^⚠: Returns the real size of the previously-allocated memory region referenced by ptr.
mallocx^⚠: Allocates at least size bytes of memory according to flags.
nallocx^⚠: Returns the real size of the allocation that would result from a mallocx function call with the same arguments.
posix_memalign^⚠: Allocates size bytes of memory at an address which is a multiple of alignment and is placed in *ptr.
rallocx^⚠: Resizes the previously-allocated memory region referenced by ptr to be at least size bytes.
realloc^⚠: Resizes the previously-allocated memory region referenced by ptr to size bytes.
sallocx^⚠: Returns the real size of the previously-allocated memory region referenced by ptr.
sdallocx^⚠: Deallocates previously-allocated memory region referenced by ptr with size hint.
xallocx^⚠: Resizes the previously-allocated memory region referenced by ptr in place to be at least size bytes, returning the real size of the allocation.

Type Aliases§

extent_alloc_t: Extent allocation function.
extent_commit_t: Extent commit function.
extent_dalloc_t: Extent deallocation function.
extent_decommit_t: Extent decommit function.
extent_destroy_t: Extent destruction function.
extent_hooks_t: Extent lifetime management functions.
extent_merge_t: Extent merge function.
extent_purge_t: Extent purge function.
extent_split_t: Extent split function.