[HttpCache] Store some memcache info to memory dumps for debugging

net/disk_cache/backend_unittest.cc

Index: net/disk_cache/backend_unittest.cc
diff --git a/net/disk_cache/backend_unittest.cc b/net/disk_cache/backend_unittest.cc
index 20fa69ae349087155c05bf5ecd6cf51aaab52710..3074ab76ec00372eb7e0d31322ff89d528c02504 100644
--- a/net/disk_cache/backend_unittest.cc
+++ b/net/disk_cache/backend_unittest.cc
@@ -18,7 +18,7 @@
 #include "base/threading/platform_thread.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/threading/thread_task_runner_handle.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/net_errors.h"
@@ -326,7 +326,11 @@ void DiskCacheBackendTest::BackendBasics() {
   entry1 = NULL;
   // base::trace_event::EstimateMemoryUsage(cache_) is added to make sure

[ssid, 2017/03/27 18:59:41]

Is this comment still valid?

[jkarlin, 2017/03/28 15:09:45]

Removed.

   // tracking memory doesn't introduce crashes.
-  EXPECT_LT(0u, base::trace_event::EstimateMemoryUsage(cache_));
+  base::trace_event::MemoryDumpArgs args = {
+      base::trace_event::MemoryDumpLevelOfDetail::DETAILED};

[xunjieli, 2017/03/27 18:29:06]

Could you run this with base::trace_event::MemoryDumpLevelOfDetail::BACKGROUND ?

If you do that, you can pass parent_absolute_name =
"net/url_request_context_0x123/http_cache" (or
"net/url_request_context/main/0x123/http_cache" if my CL lands before yours) to
cache_->DumpMemoryStats()

The BACKGROUND mode will additionally assert that any sub dumps created will be
whitelisted.

[jkarlin, 2017/03/28 15:09:45]

Done, and broke it out into separate tests.

+  base::trace_event::ProcessMemoryDump pmd(nullptr, args);
+  ASSERT_LT(0u, cache_->DumpMemoryStats(&pmd, ""));
+  EXPECT_LT(0u, pmd.allocator_dumps().size());
 
   ASSERT_THAT(OpenEntry("the first key", &entry1), IsOk());
   ASSERT_TRUE(NULL != entry1);
@@ -340,20 +344,20 @@ void DiskCacheBackendTest::BackendBasics() {
   ASSERT_TRUE(NULL != entry1);
   ASSERT_TRUE(NULL != entry2);
   EXPECT_EQ(2, cache_->GetEntryCount());
-  EXPECT_LT(0u, base::trace_event::EstimateMemoryUsage(cache_));
+  base::trace_event::ProcessMemoryDump pmd2(nullptr, args);
+  ASSERT_LT(0u, cache_->DumpMemoryStats(&pmd2, ""));
+  EXPECT_LT(0u, pmd2.allocator_dumps().size());
 
   disk_cache::Entry* entry3 = NULL;
   ASSERT_THAT(OpenEntry("some other key", &entry3), IsOk());
   ASSERT_TRUE(NULL != entry3);
   EXPECT_TRUE(entry2 == entry3);
-  EXPECT_LT(0u, base::trace_event::EstimateMemoryUsage(cache_));
 
   EXPECT_THAT(DoomEntry("some other key"), IsOk());
   EXPECT_EQ(1, cache_->GetEntryCount());
   entry1->Close();
   entry2->Close();
   entry3->Close();
-  EXPECT_LT(0u, base::trace_event::EstimateMemoryUsage(cache_));
 
   EXPECT_THAT(DoomEntry("the first key"), IsOk());
   EXPECT_EQ(0, cache_->GetEntryCount());
@@ -365,7 +369,6 @@ void DiskCacheBackendTest::BackendBasics() {
   EXPECT_THAT(DoomEntry("some other key"), IsOk());
   EXPECT_EQ(0, cache_->GetEntryCount());
   entry2->Close();
-  EXPECT_LT(0u, base::trace_event::EstimateMemoryUsage(cache_));
 }
 
 TEST_F(DiskCacheBackendTest, Basics) {