Index: components/sync/protocol/proto_memory_estimations.cc |
diff --git a/components/sync/protocol/proto_memory_estimations.cc b/components/sync/protocol/proto_memory_estimations.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..f759f986d8f6482ca5100632aa6674e1ec8c8caa |
--- /dev/null |
+++ b/components/sync/protocol/proto_memory_estimations.cc |
@@ -0,0 +1,126 @@ |
+// Copyright (c) 2016 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+// Keep this file in sync with the .proto files in this directory. |
+ |
+#include "components/sync/protocol/proto_memory_estimations.h" |
+ |
+#include "base/trace_event/memory_usage_estimator.h" |
+#include "components/sync/protocol/proto_visitors.h" |
+ |
+namespace { |
+ |
+// This class is a VisitProtoFields()-compatible visitor that estimates |
+// proto's memory usage: |
+// |
+// MemoryUsageVisitor visitor; |
+// VisitProtoFields(visitor, proto); |
+// size_t memory_usage = visitor.memory_usage(); |
+// |
+class MemoryUsageVisitor { |
+ public: |
+ MemoryUsageVisitor() : memory_usage_(0) {} |
+ |
+ size_t memory_usage() const { return memory_usage_; } |
+ |
+ template <class P> |
+ void VisitBytes(const P& parent_proto, |
+ const char* field_name, |
+ const std::string& field) { |
+ // Delegate to Visit(..., const std::string&) below. |
+ Visit(parent_proto, field_name, field); |
+ } |
+ |
+ template <class P, class E> |
+ void VisitEnum(const P&, const char* field_name, E field) {} |
+ |
+ // Types derived from MessageLite (i.e. protos) |
+ template <class P, class F> |
+ typename std::enable_if< |
+ std::is_base_of<google::protobuf::MessageLite, F>::value>::type |
+ Visit(const P&, const char* field_name, const F& field) { |
+ using base::trace_event::EstimateMemoryUsage; |
+ // All object fields are dynamically allocated. |
+ memory_usage_ += sizeof(F) + EstimateMemoryUsage(field); |
+ } |
+ |
+ // Integral types |
+ template <class P, class F> |
+ typename std::enable_if<std::is_integral<F>::value>::type |
+ Visit(const P&, const char* field_name, const F& field) { |
+ // Integral fields (integers, floats & bool) don't allocate. |
+ } |
+ |
+ // std::string |
+ template <class P> |
+ void Visit(const P&, const char* field_name, const std::string& field) { |
+ using base::trace_event::EstimateMemoryUsage; |
+ // All strings are of type ArenaStringPtr, which essentially |
+ // is std::string*. |
+ memory_usage_ += sizeof(std::string) + EstimateMemoryUsage(field); |
+ } |
+ |
+ // RepeatedPtrField |
+ template <class P, class F> |
+ void Visit(const P&, |
+ const char* field_name, |
+ const google::protobuf::RepeatedPtrField<F>& fields) { |
+ using base::trace_event::EstimateMemoryUsage; |
+ // Can't use RepeatedPtrField::SpaceUsedExcludingSelf() because it will |
+ // end up calling undefined TypeHandler::SpaceUsed() method. |
+ memory_usage_ += fields.Capacity() ? sizeof(void*) : 0; // header |
+ memory_usage_ += fields.Capacity() * sizeof(void*); |
+ for (const auto& field : fields) { |
+ memory_usage_ += sizeof(F) + EstimateMemoryUsage(field); |
+ } |
+ } |
+ |
+ // RepeatedField<integral type> |
+ template <class P, class F> |
+ typename std::enable_if<std::is_integral<F>::value>::type Visit( |
+ const P&, |
+ const char* field_name, |
+ const google::protobuf::RepeatedField<F>& fields) { |
+ memory_usage_ += fields.SpaceUsedExcludingSelf(); |
+ // Integral fields (integers, floats & bool) don't allocate, so no |
+ // point in iterating over |fields|. |
+ } |
+ |
+ // RepeatedField<std::string> |
+ template <class P> |
+ void Visit(const P&, |
+ const char* field_name, |
+ const google::protobuf::RepeatedField<std::string>& fields) { |
+ using base::trace_event::EstimateMemoryUsage; |
+ memory_usage_ += fields.SpaceUsedExcludingSelf(); |
+ for (const auto& field : fields) { |
+ memory_usage_ += EstimateMemoryUsage(field); |
+ } |
+ } |
+ |
+ private: |
+ size_t memory_usage_; |
+}; |
+ |
+} // namespace |
+ |
+namespace sync_pb { |
+ |
+template <class P> |
+size_t EstimateMemoryUsage(const P& proto) { |
+ MemoryUsageVisitor visitor; |
+ syncer::VisitProtoFields(visitor, proto); |
+ return visitor.memory_usage(); |
+} |
+ |
+// Explicit instantiations |
+ |
+#define INSTANTIATE(Proto) \ |
+ template size_t EstimateMemoryUsage<Proto>(const Proto&); |
+ |
+INSTANTIATE(EntitySpecifics) |
+INSTANTIATE(AttachmentMetadata) |
+INSTANTIATE(DataTypeContext) |
+ |
+} // namespace sync_pb |