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-rw-r--r--absl/container/internal/hashtablez_sampler.cc1
-rw-r--r--absl/container/internal/hashtablez_sampler.h25
-rw-r--r--absl/container/internal/hashtablez_sampler_test.cc19
-rw-r--r--absl/container/internal/raw_hash_set.h13
-rw-r--r--absl/container/internal/raw_hash_set_test.cc25
-rw-r--r--absl/strings/internal/cord_rep_btree_reader.h2
6 files changed, 84 insertions, 1 deletions
diff --git a/absl/container/internal/hashtablez_sampler.cc b/absl/container/internal/hashtablez_sampler.cc
index ca03d9b6..4b133705 100644
--- a/absl/container/internal/hashtablez_sampler.cc
+++ b/absl/container/internal/hashtablez_sampler.cc
@@ -68,6 +68,7 @@ void HashtablezInfo::PrepareForSampling() {
hashes_bitwise_or.store(0, std::memory_order_relaxed);
hashes_bitwise_and.store(~size_t{}, std::memory_order_relaxed);
hashes_bitwise_xor.store(0, std::memory_order_relaxed);
+ max_reserve.store(0, std::memory_order_relaxed);
create_time = absl::Now();
// The inliner makes hardcoded skip_count difficult (especially when combined
diff --git a/absl/container/internal/hashtablez_sampler.h b/absl/container/internal/hashtablez_sampler.h
index d86207f5..812118e3 100644
--- a/absl/container/internal/hashtablez_sampler.h
+++ b/absl/container/internal/hashtablez_sampler.h
@@ -80,6 +80,7 @@ struct HashtablezInfo : public profiling_internal::Sample<HashtablezInfo> {
std::atomic<size_t> hashes_bitwise_or;
std::atomic<size_t> hashes_bitwise_and;
std::atomic<size_t> hashes_bitwise_xor;
+ std::atomic<size_t> max_reserve;
// All of the fields below are set by `PrepareForSampling`, they must not be
// mutated in `Record*` functions. They are logically `const` in that sense.
@@ -107,6 +108,18 @@ inline void RecordRehashSlow(HashtablezInfo* info, size_t total_probe_length) {
std::memory_order_relaxed);
}
+inline void RecordReservationSlow(HashtablezInfo* info,
+ size_t target_capacity) {
+ info->max_reserve.store(
+ (std::max)(info->max_reserve.load(std::memory_order_relaxed),
+ target_capacity),
+ std::memory_order_relaxed);
+}
+
+inline void RecordClearedReservationSlow(HashtablezInfo* info) {
+ info->max_reserve.store(0, std::memory_order_relaxed);
+}
+
inline void RecordStorageChangedSlow(HashtablezInfo* info, size_t size,
size_t capacity) {
info->size.store(size, std::memory_order_relaxed);
@@ -170,6 +183,16 @@ class HashtablezInfoHandle {
RecordRehashSlow(info_, total_probe_length);
}
+ inline void RecordReservation(size_t target_capacity) {
+ if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
+ RecordReservationSlow(info_, target_capacity);
+ }
+
+ inline void RecordClearedReservation() {
+ if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
+ RecordClearedReservationSlow(info_);
+ }
+
inline void RecordInsert(size_t hash, size_t distance_from_desired) {
if (ABSL_PREDICT_TRUE(info_ == nullptr)) return;
RecordInsertSlow(info_, hash, distance_from_desired);
@@ -199,6 +222,8 @@ class HashtablezInfoHandle {
inline void RecordStorageChanged(size_t /*size*/, size_t /*capacity*/) {}
inline void RecordRehash(size_t /*total_probe_length*/) {}
+ inline void RecordReservation(size_t /*target_capacity*/) {}
+ inline void RecordClearedReservation() {}
inline void RecordInsert(size_t /*hash*/, size_t /*distance_from_desired*/) {}
inline void RecordErase() {}
diff --git a/absl/container/internal/hashtablez_sampler_test.cc b/absl/container/internal/hashtablez_sampler_test.cc
index 53fcfe6f..f053c19b 100644
--- a/absl/container/internal/hashtablez_sampler_test.cc
+++ b/absl/container/internal/hashtablez_sampler_test.cc
@@ -91,6 +91,7 @@ TEST(HashtablezInfoTest, PrepareForSampling) {
EXPECT_EQ(info.hashes_bitwise_or.load(), 0);
EXPECT_EQ(info.hashes_bitwise_and.load(), ~size_t{});
EXPECT_EQ(info.hashes_bitwise_xor.load(), 0);
+ EXPECT_EQ(info.max_reserve.load(), 0);
EXPECT_GE(info.create_time, test_start);
info.capacity.store(1, std::memory_order_relaxed);
@@ -101,6 +102,7 @@ TEST(HashtablezInfoTest, PrepareForSampling) {
info.hashes_bitwise_or.store(1, std::memory_order_relaxed);
info.hashes_bitwise_and.store(1, std::memory_order_relaxed);
info.hashes_bitwise_xor.store(1, std::memory_order_relaxed);
+ info.max_reserve.store(1, std::memory_order_relaxed);
info.create_time = test_start - absl::Hours(20);
info.PrepareForSampling();
@@ -113,6 +115,7 @@ TEST(HashtablezInfoTest, PrepareForSampling) {
EXPECT_EQ(info.hashes_bitwise_or.load(), 0);
EXPECT_EQ(info.hashes_bitwise_and.load(), ~size_t{});
EXPECT_EQ(info.hashes_bitwise_xor.load(), 0);
+ EXPECT_EQ(info.max_reserve.load(), 0);
EXPECT_GE(info.create_time, test_start);
}
@@ -187,6 +190,22 @@ TEST(HashtablezInfoTest, RecordRehash) {
EXPECT_EQ(info.num_rehashes.load(), 1);
}
+TEST(HashtablezInfoTest, RecordReservation) {
+ HashtablezInfo info;
+ absl::MutexLock l(&info.init_mu);
+ info.PrepareForSampling();
+ RecordReservationSlow(&info, 3);
+ EXPECT_EQ(info.max_reserve.load(), 3);
+
+ RecordReservationSlow(&info, 2);
+ // High watermark does not change
+ EXPECT_EQ(info.max_reserve.load(), 3);
+
+ RecordReservationSlow(&info, 10);
+ // High watermark does change
+ EXPECT_EQ(info.max_reserve.load(), 10);
+}
+
#if defined(ABSL_INTERNAL_HASHTABLEZ_SAMPLE)
TEST(HashtablezSamplerTest, SmallSampleParameter) {
SetHashtablezEnabled(true);
diff --git a/absl/container/internal/raw_hash_set.h b/absl/container/internal/raw_hash_set.h
index f4919ce3..212052ea 100644
--- a/absl/container/internal/raw_hash_set.h
+++ b/absl/container/internal/raw_hash_set.h
@@ -1069,6 +1069,8 @@ class raw_hash_set {
// past that we simply deallocate the array.
if (capacity_ > 127) {
destroy_slots();
+
+ infoz().RecordClearedReservation();
} else if (capacity_) {
for (size_t i = 0; i != capacity_; ++i) {
if (IsFull(ctrl_[i])) {
@@ -1382,14 +1384,20 @@ class raw_hash_set {
if (n == 0 && size_ == 0) {
destroy_slots();
infoz().RecordStorageChanged(0, 0);
+ infoz().RecordClearedReservation();
return;
}
+
// bitor is a faster way of doing `max` here. We will round up to the next
// power-of-2-minus-1, so bitor is good enough.
auto m = NormalizeCapacity(n | GrowthToLowerboundCapacity(size()));
// n == 0 unconditionally rehashes as per the standard.
if (n == 0 || m > capacity_) {
resize(m);
+
+ // This is after resize, to ensure that we have completed the allocation
+ // and have potentially sampled the hashtable.
+ infoz().RecordReservation(n);
}
}
@@ -1397,6 +1405,10 @@ class raw_hash_set {
if (n > size() + growth_left()) {
size_t m = GrowthToLowerboundCapacity(n);
resize(NormalizeCapacity(m));
+
+ // This is after resize, to ensure that we have completed the allocation
+ // and have potentially sampled the hashtable.
+ infoz().RecordReservation(n);
}
}
@@ -1638,6 +1650,7 @@ class raw_hash_set {
PolicyTraits::destroy(&alloc_ref(), slots_ + i);
}
}
+
// Unpoison before returning the memory to the allocator.
SanitizerUnpoisonMemoryRegion(slots_, sizeof(slot_type) * capacity_);
Deallocate<alignof(slot_type)>(
diff --git a/absl/container/internal/raw_hash_set_test.cc b/absl/container/internal/raw_hash_set_test.cc
index 4012a3aa..b46c4920 100644
--- a/absl/container/internal/raw_hash_set_test.cc
+++ b/absl/container/internal/raw_hash_set_test.cc
@@ -2049,15 +2049,31 @@ TEST(RawHashSamplerTest, Sample) {
std::vector<IntTable> tables;
for (int i = 0; i < 1000000; ++i) {
tables.emplace_back();
+
+ const bool do_reserve = (i % 10 > 5);
+ const bool do_rehash = !do_reserve && (i % 10 > 0);
+
+ if (do_reserve) {
+ // Don't reserve on all tables.
+ tables.back().reserve(10 * (i % 10));
+ }
+
tables.back().insert(1);
tables.back().insert(i % 5);
+
+ if (do_rehash) {
+ // Rehash some other tables.
+ tables.back().rehash(10 * (i % 10));
+ }
}
size_t end_size = 0;
std::unordered_map<size_t, int> observed_checksums;
+ std::unordered_map<ssize_t, int> reservations;
end_size += sampler.Iterate([&](const HashtablezInfo& info) {
if (preexisting_info.count(&info) == 0) {
observed_checksums[info.hashes_bitwise_xor.load(
std::memory_order_relaxed)]++;
+ reservations[info.max_reserve.load(std::memory_order_relaxed)]++;
}
++end_size;
});
@@ -2068,6 +2084,15 @@ TEST(RawHashSamplerTest, Sample) {
for (const auto& [_, count] : observed_checksums) {
EXPECT_NEAR((100 * count) / static_cast<double>(tables.size()), 0.2, 0.05);
}
+
+ EXPECT_EQ(reservations.size(), 10);
+ for (const auto& [reservation, count] : reservations) {
+ EXPECT_GE(reservation, 0);
+ EXPECT_LT(reservation, 100);
+
+ EXPECT_NEAR((100 * count) / static_cast<double>(tables.size()), 0.1, 0.05)
+ << reservation;
+ }
}
#endif // ABSL_INTERNAL_HASHTABLEZ_SAMPLE
diff --git a/absl/strings/internal/cord_rep_btree_reader.h b/absl/strings/internal/cord_rep_btree_reader.h
index 66e97f5d..7aa79dbf 100644
--- a/absl/strings/internal/cord_rep_btree_reader.h
+++ b/absl/strings/internal/cord_rep_btree_reader.h
@@ -166,7 +166,7 @@ inline size_t CordRepBtreeReader::length() const {
inline absl::string_view CordRepBtreeReader::Init(CordRepBtree* tree) {
assert(tree != nullptr);
const CordRep* edge = navigator_.InitFirst(tree);
- remaining_ = tree->length - edge->length;;
+ remaining_ = tree->length - edge->length;
return CordRepBtree::EdgeData(edge);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-24 12:45:25 +0000