Intern class IDs. This way they compress better.
(cherry picked from commit 614bffcb316c36bdffd3d5d46b405e3721639e04)
Bug: 157638573
Test: Flash flame. Get heap graph.
Change-Id: I8ac3391394aa68cc0ca846e6ab34963c6ca313f4
Merged-In: I8ac3391394aa68cc0ca846e6ab34963c6ca313f4
diff --git a/perfetto_hprof/perfetto_hprof.cc b/perfetto_hprof/perfetto_hprof.cc
index 9617497..931d5c3 100644
--- a/perfetto_hprof/perfetto_hprof.cc
+++ b/perfetto_hprof/perfetto_hprof.cc
@@ -83,8 +83,8 @@
int g_signal_pipe_fds[2];
static struct sigaction g_orig_act = {};
-uint64_t FindOrAppend(std::map<std::string, uint64_t>* m,
- const std::string& s) {
+template <typename T>
+uint64_t FindOrAppend(std::map<T, uint64_t>* m, const T& s) {
auto it = m->find(s);
if (it == m->end()) {
std::tie(it, std::ignore) = m->emplace(s, m->size());
@@ -510,6 +510,7 @@
// (default proto value for a string).
std::map<std::string, uint64_t> interned_fields{{"", 0}};
std::map<std::string, uint64_t> interned_locations{{"", 0}};
+ std::map<uintptr_t, uint64_t> interned_classes{{0, 0}};
std::map<art::RootType, std::vector<art::mirror::Object*>> root_objects;
RootFinder rcf(&root_objects);
@@ -535,20 +536,21 @@
art::Runtime::Current()->GetHeap()->VisitObjectsPaused(
[&writer, &interned_fields, &interned_locations,
- &reference_field_ids, &reference_object_ids](
+ &reference_field_ids, &reference_object_ids, &interned_classes](
art::mirror::Object* obj) REQUIRES_SHARED(art::Locks::mutator_lock_) {
if (obj->IsClass()) {
art::mirror::Class* klass = obj->AsClass().Ptr();
perfetto::protos::pbzero::HeapGraphType* type_proto =
writer.GetHeapGraph()->add_types();
- type_proto->set_id(reinterpret_cast<uintptr_t>(klass));
+ type_proto->set_id(FindOrAppend(&interned_classes,
+ reinterpret_cast<uintptr_t>(klass)));
type_proto->set_class_name(PrettyType(klass));
type_proto->set_location_id(FindOrAppend(&interned_locations,
klass->GetLocation()));
}
art::mirror::Class* klass = obj->GetClass();
- uintptr_t class_id = reinterpret_cast<uintptr_t>(klass);
+ uintptr_t class_ptr = reinterpret_cast<uintptr_t>(klass);
// We need to synethesize a new type for Class<Foo>, which does not exist
// in the runtime. Otherwise, all the static members of all classes would be
// attributed to java.lang.Class.
@@ -558,13 +560,16 @@
writer.GetHeapGraph()->add_types();
// All pointers are at least multiples of two, so this way we can make sure
// we are not colliding with a real class.
- class_id = reinterpret_cast<uintptr_t>(obj) | 1;
+ class_ptr = reinterpret_cast<uintptr_t>(obj) | 1;
+ auto class_id = FindOrAppend(&interned_classes, class_ptr);
type_proto->set_id(class_id);
type_proto->set_class_name(obj->PrettyTypeOf());
type_proto->set_location_id(FindOrAppend(&interned_locations,
obj->AsClass()->GetLocation()));
}
+ auto class_id = FindOrAppend(&interned_classes, class_ptr);
+
perfetto::protos::pbzero::HeapGraphObject* object_proto =
writer.GetHeapGraph()->add_objects();
object_proto->set_id(reinterpret_cast<uintptr_t>(obj));
