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authorRickard Green <[email protected]>2015-11-13 09:53:51 +0100
committerRickard Green <[email protected]>2015-11-13 09:53:51 +0100
commitcbad4a1be72c75a452a3d70d57bf1c1145c08ad9 (patch)
tree359cdd90d063bff84d6e7ef9ea81f2ef81acb67c /erts/emulator/beam/erl_gc.c
parentc66844d145177fbb65bcc101a9962e5a5673c162 (diff)
parent9c6f45b901ee701553afe34c0b33b7d931d73fd9 (diff)
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Merge branch 'rickard/gc-bump-reds/OTP-13097'
* rickard/gc-bump-reds/OTP-13097: Bump reductions on GC
Diffstat (limited to 'erts/emulator/beam/erl_gc.c')
-rw-r--r--erts/emulator/beam/erl_gc.c126
1 files changed, 84 insertions, 42 deletions
diff --git a/erts/emulator/beam/erl_gc.c b/erts/emulator/beam/erl_gc.c
index c8f40ee162..6cb37752bc 100644
--- a/erts/emulator/beam/erl_gc.c
+++ b/erts/emulator/beam/erl_gc.c
@@ -135,7 +135,7 @@ static Eterm* sweep_literals_to_old_heap(Eterm* heap_ptr, Eterm* heap_end, Eterm
char* src, Uint src_size);
static Eterm* collect_live_heap_frags(Process* p, ErlHeapFragment *live_hf_end,
Eterm* heap, Eterm* htop, Eterm* objv, int nobj);
-static void adjust_after_fullsweep(Process *p, int need, Eterm *objv, int nobj);
+static int adjust_after_fullsweep(Process *p, int need, Eterm *objv, int nobj);
static void shrink_new_heap(Process *p, Uint new_sz, Eterm *objv, int nobj);
static void grow_new_heap(Process *p, Uint new_sz, Eterm* objv, int nobj);
static void sweep_off_heap(Process *p, int fullsweep);
@@ -172,6 +172,20 @@ typedef struct {
erts_smp_atomic32_t refc;
} ErtsGCInfoReq;
+static ERTS_INLINE int
+gc_cost(Uint gc_moved_live_words, Uint resize_moved_words)
+{
+ Sint reds;
+
+ reds = gc_moved_live_words/10;
+ reds += resize_moved_words/100;
+ if (reds < 1)
+ return 1;
+ if (reds > INT_MAX)
+ return INT_MAX;
+ return (int) reds;
+}
+
ERTS_SCHED_PREF_QUICK_ALLOC_IMPL(gcireq,
ErtsGCInfoReq,
5,
@@ -413,6 +427,7 @@ static ERTS_INLINE void reset_active_writer(Process *p)
}
#define ERTS_DELAY_GC_EXTRA_FREE 40
+#define ERTS_ABANDON_HEAP_COST 10
static int
delay_garbage_collection(Process *p, ErlHeapFragment *live_hf_end, int need)
@@ -421,6 +436,7 @@ delay_garbage_collection(Process *p, ErlHeapFragment *live_hf_end, int need)
Eterm *orig_heap, *orig_hend, *orig_htop, *orig_stop;
Eterm *stop, *hend;
Uint hsz, ssz;
+ int reds_left;
ERTS_HOLE_CHECK(p);
@@ -482,7 +498,12 @@ delay_garbage_collection(Process *p, ErlHeapFragment *live_hf_end, int need)
/* Make sure that we do a proper GC as soon as possible... */
p->flags |= F_FORCE_GC;
- return CONTEXT_REDS;
+ reds_left = ERTS_BIF_REDS_LEFT(p);
+ if (reds_left > ERTS_ABANDON_HEAP_COST) {
+ int vreds = reds_left - ERTS_ABANDON_HEAP_COST;
+ ERTS_VBUMP_REDS(p, vreds);
+ }
+ return ERTS_ABANDON_HEAP_COST;
}
static ERTS_FORCE_INLINE Uint
@@ -536,7 +557,7 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
int need, Eterm* objv, int nobj)
{
Uint reclaimed_now = 0;
- int done = 0;
+ int reds;
ErtsMonotonicTime start_time = 0; /* Shut up faulty warning... */
ErtsSchedulerData *esdp;
#ifdef USE_VM_PROBES
@@ -562,9 +583,7 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
ERTS_CHK_OFFHEAP(p);
ErtsGcQuickSanityCheck(p);
- if (GEN_GCS(p) >= MAX_GEN_GCS(p)) {
- FLAGS(p) |= F_NEED_FULLSWEEP;
- }
+
#ifdef USE_VM_PROBES
*pidbuf = '\0';
if (DTRACE_ENABLED(gc_major_start)
@@ -577,17 +596,21 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
/*
* Test which type of GC to do.
*/
- while (!done) {
- if ((FLAGS(p) & F_NEED_FULLSWEEP) != 0) {
- DTRACE2(gc_major_start, pidbuf, need);
- done = major_collection(p, live_hf_end, need, objv, nobj, &reclaimed_now);
- DTRACE2(gc_major_end, pidbuf, reclaimed_now);
- } else {
- DTRACE2(gc_minor_start, pidbuf, need);
- done = minor_collection(p, live_hf_end, need, objv, nobj, &reclaimed_now);
- DTRACE2(gc_minor_end, pidbuf, reclaimed_now);
- }
+
+ if (GEN_GCS(p) < MAX_GEN_GCS(p) && !(FLAGS(p) & F_NEED_FULLSWEEP)) {
+ DTRACE2(gc_minor_start, pidbuf, need);
+ reds = minor_collection(p, live_hf_end, need, objv, nobj, &reclaimed_now);
+ DTRACE2(gc_minor_end, pidbuf, reclaimed_now);
+ if (reds < 0)
+ goto do_major_collection;
+ }
+ else {
+ do_major_collection:
+ DTRACE2(gc_major_start, pidbuf, need);
+ reds = major_collection(p, live_hf_end, need, objv, nobj, &reclaimed_now);
+ DTRACE2(gc_major_end, pidbuf, reclaimed_now);
}
+
reset_active_writer(p);
/*
@@ -648,23 +671,22 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
p->last_old_htop = p->old_htop;
#endif
- /* FIXME: This function should really return an Sint, i.e., a possibly
- 64 bit wide signed integer, but that requires updating all the code
- that calls it. For now, we just return INT_MAX if the result is too
- large for an int. */
- {
- Sint result = (HEAP_TOP(p) - HEAP_START(p)) / 10;
- if (result >= INT_MAX) return INT_MAX;
- else return (int) result;
- }
+ return reds;
}
int
-erts_garbage_collect(Process* p, int need, Eterm* objv, int nobj)
+erts_garbage_collect_nobump(Process* p, int need, Eterm* objv, int nobj)
{
return garbage_collect(p, ERTS_INVALID_HFRAG_PTR, need, objv, nobj);
}
+void
+erts_garbage_collect(Process* p, int need, Eterm* objv, int nobj)
+{
+ int reds = garbage_collect(p, ERTS_INVALID_HFRAG_PTR, need, objv, nobj);
+ BUMP_REDS(p, reds);
+}
+
/*
* Place all living data on a the new heap; deallocate any old heap.
* Meant to be used by hibernate/3.
@@ -679,6 +701,7 @@ erts_garbage_collect_hibernate(Process* p)
char* area;
Uint area_size;
Sint offs;
+ int reds;
if (p->flags & F_DISABLE_GC)
ERTS_INTERNAL_ERROR("GC disabled");
@@ -774,6 +797,9 @@ erts_garbage_collect_hibernate(Process* p)
ErtsGcQuickSanityCheck(p);
erts_smp_atomic32_read_band_nob(&p->state, ~ERTS_PSFLG_GC);
+
+ reds = gc_cost(actual_size, actual_size);
+ BUMP_REDS(p, reds);
}
@@ -988,16 +1014,21 @@ minor_collection(Process* p, ErlHeapFragment *live_hf_end,
if (OLD_HEAP(p) &&
((mature_size <= OLD_HEND(p) - OLD_HTOP(p)) &&
((BIN_OLD_VHEAP_SZ(p) > BIN_OLD_VHEAP(p))) ) ) {
- Uint stack_size, size_after, need_after, new_sz;
+ Eterm *prev_old_htop;
+ Uint stack_size, size_after, adjust_size, need_after, new_sz, new_mature;
stack_size = p->hend - p->stop;
new_sz = stack_size + size_before;
new_sz = next_heap_size(p, new_sz, 0);
+ prev_old_htop = p->old_htop;
do_minor(p, live_hf_end, (char *) mature, mature_size*sizeof(Eterm),
new_sz, objv, nobj);
- size_after = HEAP_TOP(p) - HEAP_START(p);
+ new_mature = p->old_htop - prev_old_htop;
+
+ size_after = new_mature;
+ size_after += HEAP_TOP(p) - HEAP_START(p);
*recl += (size_before - size_after);
ErtsGcQuickSanityCheck(p);
@@ -1016,6 +1047,8 @@ minor_collection(Process* p, ErlHeapFragment *live_hf_end,
* the heap size is substantial, we don't want to shrink.
*/
+ adjust_size = 0;
+
if ((HEAP_SIZE(p) > 3000) && (4 * need_after < HEAP_SIZE(p)) &&
((HEAP_SIZE(p) > 8000) ||
(HEAP_SIZE(p) > (OLD_HEND(p) - OLD_HEAP(p))))) {
@@ -1037,31 +1070,33 @@ minor_collection(Process* p, ErlHeapFragment *live_hf_end,
: next_heap_size(p, wanted, 0);
if (wanted < HEAP_SIZE(p)) {
shrink_new_heap(p, wanted, objv, nobj);
+ adjust_size = p->htop - p->heap;
}
- ASSERT(HEAP_SIZE(p) == next_heap_size(p, HEAP_SIZE(p), 0));
- ASSERT(MBUF(p) == NULL);
- return 1; /* We are done. */
+ goto done;
}
if (HEAP_SIZE(p) >= need_after) {
/*
* The heap size turned out to be just right. We are done.
*/
- ASSERT(HEAP_SIZE(p) == next_heap_size(p, HEAP_SIZE(p), 0));
- ASSERT(MBUF(p) == NULL);
- return 1;
+ goto done;
}
grow_new_heap(p, next_heap_size(p, need_after, 0), objv, nobj);
- return 1;
+ adjust_size = p->htop - p->heap;
+
+ done:
+ ASSERT(HEAP_SIZE(p) == next_heap_size(p, HEAP_SIZE(p), 0));
+ ASSERT(MBUF(p) == NULL);
+
+ return gc_cost(size_after, adjust_size);
}
/*
* Not enough room for a minor collection. Must force a major collection.
*/
- FLAGS(p) |= F_NEED_FULLSWEEP;
- return 0;
+ return -1;
}
/*
@@ -1340,12 +1375,13 @@ static int
major_collection(Process* p, ErlHeapFragment *live_hf_end,
int need, Eterm* objv, int nobj, Uint *recl)
{
- Uint size_before, stack_size;
+ Uint size_before, size_after, stack_size;
Eterm* n_heap;
Eterm* n_htop;
char* oh = (char *) OLD_HEAP(p);
Uint oh_size = (char *) OLD_HTOP(p) - oh;
Uint new_sz, stk_sz;
+ int adjusted;
/*
* Do a fullsweep GC. First figure out the size of the heap
@@ -1412,9 +1448,10 @@ major_collection(Process* p, ErlHeapFragment *live_hf_end,
ErtsGcQuickSanityCheck(p);
- *recl += size_before - (HEAP_TOP(p) - HEAP_START(p));
+ size_after = HEAP_TOP(p) - HEAP_START(p);
+ *recl += size_before - size_after;
- adjust_after_fullsweep(p, need, objv, nobj);
+ adjusted = adjust_after_fullsweep(p, need, objv, nobj);
#ifdef HARDDEBUG
disallow_heap_frag_ref_in_heap(p);
@@ -1422,7 +1459,8 @@ major_collection(Process* p, ErlHeapFragment *live_hf_end,
remove_message_buffers(p);
ErtsGcQuickSanityCheck(p);
- return 1; /* We are done. */
+
+ return gc_cost(size_after, adjusted ? size_after : 0);
}
static Eterm *
@@ -1523,9 +1561,10 @@ full_sweep_heaps(Process *p,
return n_htop;
}
-static void
+static int
adjust_after_fullsweep(Process *p, int need, Eterm *objv, int nobj)
{
+ int adjusted = 0;
Uint wanted, sz, need_after;
Uint stack_size = STACK_SZ_ON_HEAP(p);
@@ -1538,6 +1577,7 @@ adjust_after_fullsweep(Process *p, int need, Eterm *objv, int nobj)
/* Too small - grow to match requested need */
sz = next_heap_size(p, need_after, 0);
grow_new_heap(p, sz, objv, nobj);
+ adjusted = 1;
} else if (3 * HEAP_SIZE(p) < 4 * need_after){
/* Need more than 75% of current, postpone to next GC.*/
FLAGS(p) |= F_HEAP_GROW;
@@ -1554,8 +1594,10 @@ adjust_after_fullsweep(Process *p, int need, Eterm *objv, int nobj)
if (sz < HEAP_SIZE(p)) {
shrink_new_heap(p, sz, objv, nobj);
+ adjusted = 1;
}
}
+ return adjusted;
}
/*