Disk cache: Instead of saving the cache stats only when

the destructor is called, store them each five minutes.

From the dev channel, 15% of the runs the disk cache destructor
is not called, so the stats are not that reliable without
this change.

Review URL: http://codereview.chromium.org/42373

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@12043 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 22 insertions, 11 deletions

diff --git a/net/disk_cache/backend_impl.cc b/net/disk_cache/backend_impl.cc
index 885f1db..5801d40 100644
--- a/net/disk_cache/backend_impl.cc
+++ b/net/disk_cache/backend_impl.cc
@@ -729,6 +729,10 @@ void BackendImpl::OnStatsTimer() {
     UMA_HISTOGRAM_COUNTS(size.c_str(), data_->header.num_bytes / (1024 * 1024));
     UMA_HISTOGRAM_COUNTS(max_size.c_str(), max_size_ / (1024 * 1024));
   }
+
+  // Save stats to disk at 5 min intervals.
+  if (time % 10)
+    stats_.Store();
 }
 
 void BackendImpl::IncrementIoCount() {
diff --git a/net/disk_cache/stats.cc b/net/disk_cache/stats.cc
index 6047c5c..46c41a0 100644
--- a/net/disk_cache/stats.cc
+++ b/net/disk_cache/stats.cc
@@ -135,17 +135,7 @@ bool Stats::Init(BackendImpl* backend, uint32* storage_addr) {
 }
 
 Stats::~Stats() {
-  if (!backend_)
-    return;
-
-  OnDiskStats stats;
-  stats.signature = kDiskSignature;
-  stats.size = sizeof(stats);
-  memcpy(stats.data_sizes, data_sizes_, sizeof(data_sizes_));
-  memcpy(stats.counters, counters_, sizeof(counters_));
-
-  Addr address(storage_addr_);
-  StoreStats(backend_, address, &stats);
+  Store();
 }
 
 // The array will be filled this way:
@@ -267,4 +257,18 @@ void Stats::GetItems(StatsItems* items) {
   }
 }
 
+void Stats::Store() {
+  if (!backend_)
+    return;
+
+  OnDiskStats stats;
+  stats.signature = kDiskSignature;
+  stats.size = sizeof(stats);
+  memcpy(stats.data_sizes, data_sizes_, sizeof(data_sizes_));
+  memcpy(stats.counters, counters_, sizeof(counters_));
+
+  Addr address(storage_addr_);
+  StoreStats(backend_, address, &stats);
+}
+
 }  // namespace disk_cache
diff --git a/net/disk_cache/stats.h b/net/disk_cache/stats.h
index 84f013d..6658df6 100644
--- a/net/disk_cache/stats.h
+++ b/net/disk_cache/stats.h
@@ -60,6 +60,9 @@ class Stats {
 
   void GetItems(StatsItems* items);
 
+  // Saves the stats to disk.
+  void Store();
+
   // Support for StatsHistograms. Together, these methods allow StatsHistograms
   // to take a snapshot of the data_sizes_ as the histogram data.
   int GetBucketRange(size_t i) const;