Track SimpleCache memory usage in net/ MemoryDumpProvider

net/http/http_cache.cc

Index: net/http/http_cache.cc
diff --git a/net/http/http_cache.cc b/net/http/http_cache.cc
index b02ddf02adf0a12669426d13131ce0e33839fe58..860c4c4fcc57ca430e359a354c444a57354a26dc 100644
--- a/net/http/http_cache.cc
+++ b/net/http/http_cache.cc
@@ -28,6 +28,9 @@
 #include "base/threading/worker_pool.h"
 #include "base/time/default_clock.h"
 #include "base/time/time.h"
+#include "base/trace_event/memory_allocator_dump.h"
+#include "base/trace_event/memory_usage_estimator.h"
+#include "base/trace_event/process_memory_dump.h"
 #include "net/base/cache_type.h"
 #include "net/base/io_buffer.h"
 #include "net/base/load_flags.h"
@@ -106,6 +109,11 @@ HttpCache::ActiveEntry::~ActiveEntry() {
   }
 }
 
+size_t HttpCache::ActiveEntry::EstimateMemoryUsage() const {
+  return base::trace_event::EstimateMemoryUsage(readers) +

[jkarlin, 2017/02/17 18:13:08]

You'll need to EMU HttpCache::Transaction, which the compiler missed.

[xunjieli, 2017/02/21 15:20:39]

Acknowledged. We aren't tracking ActiveEntry per offline discussion

+         base::trace_event::EstimateMemoryUsage(pending_queue);

[jkarlin, 2017/02/17 17:43:05]

+ writer ?  EMU(writer) : 0

[xunjieli, 2017/02/21 15:20:39]

Acknowledged.

+}
+
 //-----------------------------------------------------------------------------
 
 // This structure keeps track of work items that are attempting to create or
@@ -114,6 +122,13 @@ struct HttpCache::PendingOp {
   PendingOp() : disk_entry(NULL) {}
   ~PendingOp() {}
 
+  // Returns the estimate of dynamically allocated memory in bytes.
+  size_t EstimateMemoryUsage() const {
+    return base::trace_event::EstimateMemoryUsage(backend) +
+           base::trace_event::EstimateMemoryUsage(writer) +
+           base::trace_event::EstimateMemoryUsage(pending_queue);

[jkarlin, 2017/02/17 17:43:06]

+ disk_entry ? EMU(disk_entry) : 0

[jkarlin, 2017/02/17 18:03:43]

Actually, don't do this. We're going to count the disk_entry in the backend.

[xunjieli, 2017/02/21 15:20:39]

Acknowledged.

+  }
+
   disk_cache::Entry* disk_entry;
   std::unique_ptr<disk_cache::Backend> backend;
   std::unique_ptr<WorkItem> writer;
@@ -178,6 +193,8 @@ class HttpCache::WorkItem {
   void ClearCallback() { callback_.Reset(); }
   bool Matches(Transaction* trans) const { return trans == trans_; }
   bool IsValid() const { return trans_ || entry_ || !callback_.is_null(); }
+  // Returns the estimate of dynamically allocated memory in bytes.

[jkarlin, 2017/02/17 17:43:06]

Newline above the comment

[xunjieli, 2017/02/21 15:20:39]

Done.

+  size_t EstimateMemoryUsage() const { return 0; }
 
  private:
   WorkItemOperation operation_;
@@ -481,6 +498,21 @@ HttpCache::SetHttpNetworkTransactionFactoryForTesting(
   return old_network_layer;
 }
 
+void HttpCache::DumpMemoryStats(base::trace_event::ProcessMemoryDump* pmd,
+                                const std::string& parent_absolute_name) const {
+  size_t memory_estimate =
+      base::trace_event::EstimateMemoryUsage(disk_cache_) +
+      base::trace_event::EstimateMemoryUsage(active_entries_) +
+      base::trace_event::EstimateMemoryUsage(doomed_entries_) +
+      base::trace_event::EstimateMemoryUsage(playback_cache_map_) +
+      base::trace_event::EstimateMemoryUsage(pending_ops_);

[jkarlin, 2017/02/17 17:43:06]

After F2F w/ Helen we discussed that members that don't do their own allocation
are explicitly *not* being accounted for here. Instead, the idea is to only
trace objects that can grow arbitrarily because net/ just has too much to trace
otherwise.


That's why things like clock_, backend_factory_, etc. aren't accounted for.

[xunjieli, 2017/02/21 15:20:39]

Acknowledged. I added a comment

+  base::trace_event::MemoryAllocatorDump* dump =
+      pmd->CreateAllocatorDump(parent_absolute_name + "/http_cache");
+  dump->AddScalar(base::trace_event::MemoryAllocatorDump::kNameSize,
+                  base::trace_event::MemoryAllocatorDump::kUnitsBytes,
+                  memory_estimate);
+}
+
 //-----------------------------------------------------------------------------
 
 int HttpCache::CreateBackend(disk_cache::Backend** backend,