From e3b44b75af1c1444136029687aca9b6051f3f39a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Mon, 3 Dec 2012 16:03:01 +0100 Subject: erts: Add mseg cache for large sbc segments * Not a power of two (unpowered) segements --- erts/emulator/sys/common/erl_mseg.c | 115 ++++++++++++++++++++++++++++++++---- 1 file changed, 103 insertions(+), 12 deletions(-) (limited to 'erts/emulator') diff --git a/erts/emulator/sys/common/erl_mseg.c b/erts/emulator/sys/common/erl_mseg.c index c8dd50bf7a..7db9da6aba 100644 --- a/erts/emulator/sys/common/erl_mseg.c +++ b/erts/emulator/sys/common/erl_mseg.c @@ -183,6 +183,7 @@ typedef struct ErtsMsegAllctr_t_ ErtsMsegAllctr_t; struct mem_kind_t { cache_t cache[MAX_CACHE_SIZE]; + cache_t *cache_unpowered; cache_t *cache_area[CACHE_AREAS]; cache_t *cache_free; @@ -529,13 +530,15 @@ static ERTS_INLINE void mseg_cache_free_descriptor(MemKind *mk, cache_t *c) { static ERTS_INLINE int cache_bless_segment(MemKind *mk, void *seg, Uint size) { + cache_t *c; ERTS_DBG_MK_CHK_THR_ACCESS(mk); - if (IS_2POW(size)) { - int ix = SIZE_TO_CACHE_AREA_IDX(size); - cache_t *c; - if (ix < CACHE_AREAS && mk->cache_free) { - ASSERT( (1 << (ix + MSEG_ALIGN_BITS)) == size); + if (mk->cache_free) { + if (IS_2POW(size)) { + int ix = SIZE_TO_CACHE_AREA_IDX(size); + + ASSERT(ix < CACHE_AREAS); + ASSERT((1 << (ix + MSEG_ALIGN_BITS)) == size); /* unlink from free cache list */ c = mseg_cache_alloc_descriptor(mk); @@ -548,6 +551,23 @@ static ERTS_INLINE int cache_bless_segment(MemKind *mk, void *seg, Uint size) { mk->cache_area[ix] = c; mk->cache_size++; + ASSERT(mk->cache_size <= mk->ma->max_cache_size); + + return 1; + } else { + /* unlink from free cache list */ + c = mseg_cache_alloc_descriptor(mk); + + /* link to cache area */ + c->seg = seg; + c->size = size; + c->next = mk->cache_unpowered; + + mk->cache_unpowered = c; + mk->cache_size++; + + ASSERT(mk->cache_size <= mk->ma->max_cache_size); + return 1; } } @@ -555,7 +575,9 @@ static ERTS_INLINE int cache_bless_segment(MemKind *mk, void *seg, Uint size) { return 0; } -static ERTS_INLINE void *cache_get_segment(MemKind *mk, Uint size) { +static ERTS_INLINE void *cache_get_segment(MemKind *mk, Uint *size_p) { + + Uint size = *size_p; ERTS_DBG_MK_CHK_THR_ACCESS(mk); if (IS_2POW(size)) { @@ -598,8 +620,46 @@ static ERTS_INLINE void *cache_get_segment(MemKind *mk, Uint size) { ASSERT(csize == size); return seg; } - } + } + else if (mk->cache_unpowered) { + void *seg; + cache_t *c, *pc; + Uint csize; + Uint bad_max_abs = mk->ma->abs_max_cache_bad_fit; + /* Uint bad_max_rel = mk->ma->rel_max_cache_bad_fit; */ + + c = mk->cache_unpowered; + pc = c; + + while (c) { + csize = c->size; + if (csize >= size && (csize - size) < bad_max_abs ) { + + /* unlink from cache area */ + seg = c->seg; + + + if (pc == c) { + mk->cache_unpowered = c->next; + } else { + pc->next = c->next; + } + c->next = NULL; + mk->cache_size--; + mk->cache_hits++; + + /* link to free cache list */ + mseg_cache_free_descriptor(mk, c); + *size_p = csize; + + return seg; + } + + pc = c; + c = c->next; + } + } return NULL; } @@ -607,6 +667,30 @@ static ERTS_INLINE void *cache_get_segment(MemKind *mk, Uint size) { * Slowly remove segments cached in the allocator by * using callbacks from aux-work in the scheduler. */ + +static ERTS_INLINE Uint mseg_drop_one_memkind_cache_size(MemKind *mk, cache_t **head) { + cache_t *c = NULL; + + c = *head; + + ASSERT( c != NULL ); + + *head = c->next; + + if (erts_mtrace_enabled) + erts_mtrace_crr_free(SEGTYPE, SEGTYPE, c->seg); + + mseg_destroy(mk->ma, mk, c->seg, c->size); + mseg_cache_free_descriptor(mk, c); + + mk->segments.current.watermark--; + mk->cache_size--; + + ASSERT( mk->cache_size >= 0 ); + + return mk->cache_size; +} + static ERTS_INLINE Uint mseg_drop_memkind_cache_size(MemKind *mk, int ix) { cache_t *c = NULL, *next = NULL; @@ -644,12 +728,15 @@ static ERTS_INLINE Uint mseg_drop_memkind_cache_size(MemKind *mk, int ix) { static Uint mseg_check_memkind_cache(MemKind *mk) { int i; - /* remove biggest first (less likly to be reused) */ ERTS_DBG_MK_CHK_THR_ACCESS(mk); - for (i = CACHE_AREAS - 1; i > 0; i--) { + + if (mk->cache_unpowered) + return mseg_drop_one_memkind_cache_size(mk, &(mk->cache_unpowered)); + + for (i = 0; i < CACHE_AREAS; i++) { if (mk->cache_area[i] != NULL) - return mseg_drop_memkind_cache_size(mk, i); + return mseg_drop_one_memkind_cache_size(mk, &(mk->cache_area[i])); } return 0; @@ -769,7 +856,7 @@ mseg_alloc(ErtsMsegAllctr_t *ma, ErtsAlcType_t atype, Uint *size_p, ma->min_seg_size = size; #endif - if (opt->cache && mk->cache_size > 0 && (seg = cache_get_segment(mk, size)) != NULL) + if (opt->cache && mk->cache_size > 0 && (seg = cache_get_segment(mk, &size)) != NULL) goto done; if ((seg = mseg_create(ma, mk, size)) == NULL) @@ -1451,13 +1538,17 @@ static void mem_kind_init(ErtsMsegAllctr_t *ma, MemKind* mk, const char* name) mk->cache_free = NULL; - for (i = 0; i < MAX_CACHE_SIZE; i++) { + ASSERT(ma->max_cache_size <= MAX_CACHE_SIZE); + + for (i = 0; i < ma->max_cache_size; i++) { mk->cache[i].seg = NULL; mk->cache[i].size = 0; mk->cache[i].next = mk->cache_free; mk->cache_free = &(mk->cache[i]); } + mk->cache_unpowered = NULL; + mk->cache_size = 0; mk->cache_hits = 0; -- cgit v1.2.3