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Blazing fast memory allocator designed for video games

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smmalloc

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About

smmalloc is a fast and efficient "proxy" allocator designed to handle many small allocations/deallocations in heavy multithreaded scenarios. The allocator created for using in applications where the performance is critical such as video games. Designed to speed up the typical memory allocation pattern in C++ such as many small allocations and deletions. This is a proxy allocator means that smmalloc handles only specific allocation sizes and pass-through all other allocations to generic heap allocator.

Commercial games using smmalloc

  • Warface (PS4, X1, Nintendo Switch)

Features

  • Near zero size overhead for handled allocations (allocator does not store any per-allocation meta information)
  • Blazing fast (~40 cycles per operation) when allocator thread cache is used (configurable)
  • Very simple to integrate on any platform. Just make your current allocator as fallback allocator and let the smmalloc handle specific allocations and speed up your application.
  • Highly scalable in multithread environment.

Performance

Here is an example of performance comparison for several different allocators.
Platform: Windows 10, Intel Core i7-2600

Threads #1 #2 #3 #4 #5
crt 23853865 15410410 15993655 14124607 14636381
rpmalloc 75866414 52689298 52606215 46058909 38706739
hoard 65922032 46605339 42874516 34404618 27629651
ltalloc 62525965 52315981 41634992 33557726 27333887
smmalloc 92615384 70584046 66352324 47087501 38303161
smmalloc (no thread cache) 49295774 25991465 11342809 8615216 6455889
dlmalloc + mutex 31313394 5858632 3824636 3354672 2135141
dlmalloc 106304079 0 0 0 0

Performance comparison

Here is an example of performance comparison for several different allocators.
Platform: Playstation 4

Threads #1 #2 #3 #4
mspace 4741379 956729 457264 366920
crt 4444444 853385 419009 332095
ltalloc 28571429 25290698 19248174 14683637
smmalloc 36065574 29333333 25202412 21868691
smmalloc (no thread cache) 22916667 8527132 5631815 4198497
dlmalloc + mutex 8058608 1848623 579845 564604
dlmalloc 35483871 0 0 0

Performance comparison

Usage

_sm_allocator_create - create allocator instance
_sm_allocator_destroy - destroy allocator instance
_sm_allocator_thread_cache_create - create thread cache for current thread
_sm_allocator_thread_cache_destroy - destroy thread cache for current thread
_sm_malloc - allocate aligned memory block
_sm_free - free memory block
_sm_realloc - reallocate memory block
_sm_msize - get usable memory size

Tiny code example

// create allocator to handle 16, 32, 48 and 64 allocations (4 buckets, 16Mb each) 
sm_allocator space = _sm_allocator_create(4, (16 * 1024 * 1024));

// allocate 19 bytes with 16 bytes alignment
void* p = _sm_malloc(space, 19, 16);

// free memory
_sm_free(space, p)

// destroy allocator
_sm_allocator_destroy(space);