Add BytesRead metric to CPM

chrome/browser/performance_monitor/performance_monitor.cc

Index: chrome/browser/performance_monitor/performance_monitor.cc
diff --git a/chrome/browser/performance_monitor/performance_monitor.cc b/chrome/browser/performance_monitor/performance_monitor.cc
index 38f7192ca207bead318ace9cd48800521db71a54..372ab3b9892c312330dd27f68083ef45bb8d90e1 100644
--- a/chrome/browser/performance_monitor/performance_monitor.cc
+++ b/chrome/browser/performance_monitor/performance_monitor.cc
@@ -34,6 +34,7 @@
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
 #include "content/public/browser/web_contents.h"
+#include "net/url_request/url_request.h"
 
 using content::BrowserThread;
 using extensions::Extension;
@@ -61,6 +62,10 @@ bool StringToTime(std::string time, base::Time* output) {
 
 namespace performance_monitor {
 
+bool PerformanceMonitor::initialized_ = false;
+
+PerformanceMonitor::ByteCount::ByteCount() : disk(0), network(0) { }
+
 PerformanceMonitor::PerformanceMonitor() : database_(NULL) {
 }
 
@@ -94,6 +99,18 @@ void PerformanceMonitor::Start() {
 void PerformanceMonitor::InitOnBackgroundThread() {
   CHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
   database_ = Database::Create(database_path_);
+
+  // Initialize each member of bytes_read_ to the value in the database; if
+  // there isn't a recording in the database, the value stays at 0.
+  MetricInfo info;
+  if (database_->GetRecentStatsForActivityAndMetric(METRIC_DISK_BYTES_READ,
+                                                    &info)) {
+    bytes_read_.disk = info.value;
+  }
+  if (database_->GetRecentStatsForActivityAndMetric(METRIC_NETWORK_BYTES_READ,
+                                                    &info)) {
+    bytes_read_.network = info.value;
+  }
 }
 
 void PerformanceMonitor::FinishInit() {
@@ -244,11 +261,18 @@ void PerformanceMonitor::NotifyInitialized() {
       chrome::NOTIFICATION_PERFORMANCE_MONITOR_INITIALIZED,
       content::Source<PerformanceMonitor>(this),
       content::NotificationService::NoDetails());
+
+  initialized_ = true;
 }
 
 void PerformanceMonitor::GatherStatisticsOnBackgroundThread() {
   CHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
 
+  database_->AddMetric(METRIC_DISK_BYTES_READ,
+                       base::Int64ToString(bytes_read_.disk));

[battre, 2012/08/21 20:37:33]

If you access bytes_read_ here, you must be on the IO thread.

[Devlin, 2012/08/21 22:51:52]

Done.

+  database_->AddMetric(METRIC_NETWORK_BYTES_READ,
+                       base::Int64ToString(bytes_read_.network));
+
   // Because the CPU usage is gathered as an average since the last time the
   // function was called, while the memory usage is gathered as an instantaneous
   // usage, the CPU usage is gathered before the metrics map is wiped.
@@ -362,6 +386,28 @@ void PerformanceMonitor::UpdateLiveProfilesHelper(
 
 void PerformanceMonitor::DoTimedCollections() {
   UpdateLiveProfiles();
+
+  BrowserThread::PostBlockingPoolSequencedTask(
+      Database::kDatabaseSequenceToken,
+      FROM_HERE,
+      base::Bind(&PerformanceMonitor::GatherStatisticsOnBackgroundThread,
+                 base::Unretained(this)));
+}
+
+void PerformanceMonitor::BytesRead(const net::URLRequest& request,
+                                   const int bytes_read) {
+  // Strictly speaking, we don't care that this is done on the I/O thread - we
+  // only care that it is always done on the *same* thread. This should be the
+  // only place which modifies the value of bytes_read_; thus we avoid race
+  // conditions (inserting into the database is not a race condition, because if
+  // it is not inserted in one iteration, it will be in the next, and it was
+  // close enough to justify being in either one).
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  if (request.url().SchemeIsFile())
+    bytes_read_.disk += bytes_read;
+  else
+    bytes_read_.network += bytes_read;
 }
 
 void PerformanceMonitor::Observe(int type,