From f09d1b2895966f4262a5afdab764fe790b0f9ae1 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Tue, 12 Feb 2013 15:36:46 +0100 Subject: erts: Prefer sbc segment caching over mbc segments --- erts/emulator/sys/common/erl_mseg.c | 39 +++++++++++++++++++++++++++++++++---- 1 file changed, 35 insertions(+), 4 deletions(-) (limited to 'erts/emulator/sys/common/erl_mseg.c') diff --git a/erts/emulator/sys/common/erl_mseg.c b/erts/emulator/sys/common/erl_mseg.c index 2f237153ef..32d753a67b 100644 --- a/erts/emulator/sys/common/erl_mseg.c +++ b/erts/emulator/sys/common/erl_mseg.c @@ -535,7 +535,15 @@ static ERTS_INLINE int cache_bless_segment(MemKind *mk, void *seg, Uint size, Ui ASSERT(!MSEG_FLG_IS_2POW(flags) || (MSEG_FLG_IS_2POW(flags) && MAP_IS_ALIGNED(seg) && IS_2POW(size))); + /* The idea is that sbc caching is prefered over mbc caching. + * Blocks are normally allocated in mb carriers and thus cached there. + * Large blocks has no such cache and it is up to mseg to cache them to speed things up. + */ + if (!erts_circleq_is_empty(&(mk->cache_free))) { + + /* We have free slots, use one to cache the segment */ + c = erts_circleq_head(&(mk->cache_free)); erts_circleq_remove(c); @@ -550,10 +558,8 @@ static ERTS_INLINE int cache_bless_segment(MemKind *mk, void *seg, Uint size, Ui erts_circleq_push_head(&(mk->cache_powered_node[ix]), c); - } else { - + } else erts_circleq_push_head(&(mk->cache_unpowered_node), c); - } mk->cache_size++; ASSERT(mk->cache_size <= mk->ma->max_cache_size); @@ -561,7 +567,8 @@ static ERTS_INLINE int cache_bless_segment(MemKind *mk, void *seg, Uint size, Ui return 1; } else if (!MSEG_FLG_IS_2POW(flags) && !erts_circleq_is_empty(&(mk->cache_unpowered_node))) { - /* Evict oldest slot from cache so we can store an unpowered (sbc) segment */ + /* No free slots. + * Evict oldest slot from unpowered cache so we can cache an unpowered (sbc) segment */ c = erts_circleq_tail(&(mk->cache_unpowered_node)); erts_circleq_remove(c); @@ -575,6 +582,30 @@ static ERTS_INLINE int cache_bless_segment(MemKind *mk, void *seg, Uint size, Ui erts_circleq_push_head(&(mk->cache_unpowered_node), c); return 1; + } else if (!MSEG_FLG_IS_2POW(flags)) { + + /* No free slots and no unpowered (sbc) slots. + * Evict smallest slot from powered cache so we can cache an unpowered (sbc) segment */ + + int i; + + for( i = 0; i < CACHE_AREAS; i++) { + if (erts_circleq_is_empty(&(mk->cache_powered_node[i]))) + continue; + + c = erts_circleq_tail(&(mk->cache_powered_node[i])); + erts_circleq_remove(c); + + mseg_destroy(mk->ma, mk, c->seg, c->size); + mseg_cache_clear_node(c); + + c->seg = seg; + c->size = size; + + erts_circleq_push_head(&(mk->cache_unpowered_node), c); + + return 1; + } } return 0; -- cgit v1.2.3