Reviewers: Michael Starzinger,
Message:
I have to investigate the problem in detail.
Description:
Revert "Simplifying GC heuristics, deleted old generation allocation limit."
This reverts commit dde70b769a5957e2434929cfb3ba269818252a56.
BUG=
Please review this at https://codereview.chromium.org/14750013/
SVN Base: https://v8.googlecode.com/svn/branches/bleeding_edge
Affected files:
M src/heap.h
M src/heap.cc
Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index
ab3f8a3075b0bfe517db7ae79ffa75d884a75e1b..a69c539911da64045d1cae9f109e7847d2d83b07
100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -118,7 +118,8 @@ Heap::Heap()
disallow_allocation_failure_(false),
#endif // DEBUG
new_space_high_promotion_mode_active_(false),
-
old_generation_allocation_limit_(kMinimumOldGenerationAllocationLimit),
+ old_gen_promotion_limit_(kMinimumPromotionLimit),
+ old_gen_allocation_limit_(kMinimumAllocationLimit),
size_of_old_gen_at_last_old_space_gc_(0),
external_allocation_limit_(0),
amount_of_external_allocated_memory_(0),
@@ -281,7 +282,7 @@ GarbageCollector
Heap::SelectGarbageCollector(AllocationSpace space,
}
// Is enough data promoted to justify a global GC?
- if (OldGenerationAllocationLimitReached()) {
+ if (OldGenerationPromotionLimitReached()) {
isolate_->counters()->gc_compactor_caused_by_promoted_data()->Increment();
*reason = "promotion limit reached";
return MARK_COMPACTOR;
@@ -915,8 +916,10 @@ bool Heap::PerformGarbageCollection(GarbageCollector
collector,
size_of_old_gen_at_last_old_space_gc_ = PromotedSpaceSizeOfObjects();
- old_generation_allocation_limit_ =
-
OldGenerationAllocationLimit(size_of_old_gen_at_last_old_space_gc_);
+ old_gen_promotion_limit_ =
+ OldGenPromotionLimit(size_of_old_gen_at_last_old_space_gc_);
+ old_gen_allocation_limit_ =
+ OldGenAllocationLimit(size_of_old_gen_at_last_old_space_gc_);
old_gen_exhausted_ = false;
} else {
@@ -5959,8 +5962,10 @@ void Heap::ReportHeapStatistics(const char* title) {
USE(title);
PrintF(">>>>>> =============== %s (%d) =============== >>>>>>\n",
title, gc_count_);
- PrintF("old_generation_allocation_limit_ %" V8_PTR_PREFIX "d\n",
- old_generation_allocation_limit_);
+ PrintF("old_gen_promotion_limit_ %" V8_PTR_PREFIX "d\n",
+ old_gen_promotion_limit_);
+ PrintF("old_gen_allocation_limit_ %" V8_PTR_PREFIX "d\n",
+ old_gen_allocation_limit_);
PrintF("\n");
PrintF("Number of handles : %d\n",
HandleScope::NumberOfHandles(isolate_));
Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index
9f054400a07620bcb1d93e43f4039b9a44fad5d8..b24b0b3608344ffba6177e42df6edf3c02f217e2
100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -1561,23 +1561,44 @@ class Heap {
return PromotedSpaceSizeOfObjects() + PromotedExternalMemorySize();
}
+ // True if we have reached the allocation limit in the old generation
that
+ // should force the next GC (caused normally) to be a full one.
+ inline bool OldGenerationPromotionLimitReached() {
+ return PromotedTotalSize() > old_gen_promotion_limit_;
+ }
+
inline intptr_t OldGenerationSpaceAvailable() {
- return old_generation_allocation_limit_ - PromotedTotalSize();
+ return old_gen_allocation_limit_ - PromotedTotalSize();
}
inline intptr_t OldGenerationCapacityAvailable() {
return max_old_generation_size_ - PromotedTotalSize();
}
- static const intptr_t kMinimumOldGenerationAllocationLimit =
+ static const intptr_t kMinimumPromotionLimit = 5 * Page::kPageSize;
+ static const intptr_t kMinimumAllocationLimit =
8 * (Page::kPageSize > MB ? Page::kPageSize : MB);
- intptr_t OldGenerationAllocationLimit(intptr_t old_gen_size) {
+ intptr_t OldGenPromotionLimit(intptr_t old_gen_size) {
const int divisor = FLAG_stress_compaction ? 10 :
new_space_high_promotion_mode_active_ ? 1 : 3;
intptr_t limit =
- Max(old_gen_size + old_gen_size / divisor,
- kMinimumOldGenerationAllocationLimit);
+ Max(old_gen_size + old_gen_size / divisor, kMinimumPromotionLimit);
+ limit += new_space_.Capacity();
+ // TODO(hpayer): Can be removed when when pretenuring is supported for
all
+ // allocation sites.
+ if (IsHighSurvivalRate() && IsStableOrIncreasingSurvivalTrend()) {
+ limit *= 2;
+ }
+ intptr_t halfway_to_the_max = (old_gen_size +
max_old_generation_size_) / 2;
+ return Min(limit, halfway_to_the_max);
+ }
+
+ intptr_t OldGenAllocationLimit(intptr_t old_gen_size) {
+ const int divisor = FLAG_stress_compaction ? 8 :
+ new_space_high_promotion_mode_active_ ? 1 : 2;
+ intptr_t limit =
+ Max(old_gen_size + old_gen_size / divisor,
kMinimumAllocationLimit);
limit += new_space_.Capacity();
// TODO(hpayer): Can be removed when when pretenuring is supported for
all
// allocation sites.
@@ -1658,14 +1679,22 @@ class Heap {
if (FLAG_stress_compaction && (gc_count_ & 1) != 0) return true;
+ intptr_t total_promoted = PromotedTotalSize();
+
+ intptr_t adjusted_promotion_limit =
+ old_gen_promotion_limit_ - new_space_.Capacity();
+
+ if (total_promoted >= adjusted_promotion_limit) return true;
+
intptr_t adjusted_allocation_limit =
- old_generation_allocation_limit_ - new_space_.Capacity();
+ old_gen_allocation_limit_ - new_space_.Capacity() / 5;
- if (PromotedTotalSize() >= adjusted_allocation_limit) return true;
+ if (PromotedSpaceSizeOfObjects() >= adjusted_allocation_limit) return
true;
return false;
}
+
void UpdateNewSpaceReferencesInExternalStringTable(
ExternalStringTableUpdaterCallback updater_func);
@@ -1990,9 +2019,13 @@ class Heap {
// Limit that triggers a global GC on the next (normally caused) GC.
This
// is checked when we have already decided to do a GC to help determine
- // which collector to invoke, before expanding a paged space in the old
- // generation and on every allocation in large object space.
- intptr_t old_generation_allocation_limit_;
+ // which collector to invoke.
+ intptr_t old_gen_promotion_limit_;
+
+ // Limit that triggers a global GC as soon as is reasonable. This is
+ // checked before expanding a paged space in the old generation and on
+ // every allocation in large object space.
+ intptr_t old_gen_allocation_limit_;
// Used to adjust the limits that control the timing of the next GC.
intptr_t size_of_old_gen_at_last_old_space_gc_;
@@ -2010,7 +2043,7 @@ class Heap {
// Indicates that an allocation has failed in the old generation since
the
// last GC.
- bool old_gen_exhausted_;
+ int old_gen_exhausted_;
Object* native_contexts_list_;
--
--
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