diff options
| author | Jason Evans <je@fb.com> | 2011-03-07 06:56:36 (GMT) |
|---|---|---|
| committer | Jason Evans <je@fb.com> | 2011-03-15 18:12:11 (GMT) |
| commit | 41ade967c29ea9312c0b7390ee43bc0c63373f39 (patch) | |
| tree | 1bde657dd18b33f7aad8e1d4192b5fda00717a53 /jemalloc/include | |
| parent | ff7450727f64180367f430b1b747f9e682e26df4 (diff) | |
| download | jemalloc-41ade967c29ea9312c0b7390ee43bc0c63373f39.zip jemalloc-41ade967c29ea9312c0b7390ee43bc0c63373f39.tar.gz jemalloc-41ade967c29ea9312c0b7390ee43bc0c63373f39.tar.bz2 | |
Reduce size of small_size2bin lookup table.
Convert all direct small_size2bin[...] accesses to SMALL_SIZE2BIN(...)
macro calls, and use a couple of cheap math operations to allow
compacting the table by 4X or 8X, on 32- and 64-bit systems,
respectively.
Diffstat (limited to 'jemalloc/include')
| -rw-r--r-- | jemalloc/include/jemalloc/internal/arena.h | 7 | ||||
| -rw-r--r-- | jemalloc/include/jemalloc/internal/jemalloc_internal.h.in | 4 | ||||
| -rw-r--r-- | jemalloc/include/jemalloc/internal/tcache.h | 2 |
3 files changed, 10 insertions, 3 deletions
diff --git a/jemalloc/include/jemalloc/internal/arena.h b/jemalloc/include/jemalloc/internal/arena.h index a43d1fa..78828ef 100644 --- a/jemalloc/include/jemalloc/internal/arena.h +++ b/jemalloc/include/jemalloc/internal/arena.h @@ -19,6 +19,7 @@ #ifdef JEMALLOC_TINY /* Smallest size class to support. */ # define LG_TINY_MIN LG_SIZEOF_PTR +# define TINY_MIN (1U << LG_TINY_MIN) #endif /* @@ -389,7 +390,13 @@ struct arena_s { extern size_t opt_lg_qspace_max; extern size_t opt_lg_cspace_max; extern ssize_t opt_lg_dirty_mult; +/* + * small_size2bin is a compact lookup table that rounds request sizes up to + * size classes. In order to reduce cache footprint, the table is compressed, + * and all accesses are via the SMALL_SIZE2BIN macro. + */ extern uint8_t const *small_size2bin; +#define SMALL_SIZE2BIN(s) (small_size2bin[(s-1) >> LG_TINY_MIN]) /* Various bin-related settings. */ #ifdef JEMALLOC_TINY /* Number of (2^n)-spaced tiny bins. */ diff --git a/jemalloc/include/jemalloc/internal/jemalloc_internal.h.in b/jemalloc/include/jemalloc/internal/jemalloc_internal.h.in index aab2bfb..0f58a7a 100644 --- a/jemalloc/include/jemalloc/internal/jemalloc_internal.h.in +++ b/jemalloc/include/jemalloc/internal/jemalloc_internal.h.in @@ -402,7 +402,7 @@ s2u(size_t size) { if (size <= small_maxclass) - return (arenas[0]->bins[small_size2bin[size]].reg_size); + return (arenas[0]->bins[SMALL_SIZE2BIN(size)].reg_size); if (size <= arena_maxclass) return (PAGE_CEILING(size)); return (CHUNK_CEILING(size)); @@ -448,7 +448,7 @@ sa2u(size_t size, size_t alignment, size_t *run_size_p) if (usize <= arena_maxclass && alignment <= PAGE_SIZE) { if (usize <= small_maxclass) { return - (arenas[0]->bins[small_size2bin[usize]].reg_size); + (arenas[0]->bins[SMALL_SIZE2BIN(usize)].reg_size); } return (PAGE_CEILING(usize)); } else { diff --git a/jemalloc/include/jemalloc/internal/tcache.h b/jemalloc/include/jemalloc/internal/tcache.h index f431c66..7b71172 100644 --- a/jemalloc/include/jemalloc/internal/tcache.h +++ b/jemalloc/include/jemalloc/internal/tcache.h @@ -223,7 +223,7 @@ tcache_alloc_small(tcache_t *tcache, size_t size, bool zero) size_t binind; tcache_bin_t *tbin; - binind = small_size2bin[size]; + binind = SMALL_SIZE2BIN(size); assert(binind < nbins); tbin = &tcache->tbins[binind]; ret = tcache_alloc_easy(tbin); |