SDCH: add TimeWeightedMemoryUse

net/sdch/sdch_owner.cc

Index: net/sdch/sdch_owner.cc
diff --git a/net/sdch/sdch_owner.cc b/net/sdch/sdch_owner.cc
index 9d985816a9e0350e3930b7c17e7f4f0fdbb85630..9e2ac16d2423ef3f9843d51760cade6d02ebe432 100644
--- a/net/sdch/sdch_owner.cc
+++ b/net/sdch/sdch_owner.cc
@@ -20,43 +20,6 @@ namespace net {
 
 namespace {
 
-enum DictionaryFate {
-  // A Get-Dictionary header wasn't acted on.
-  DICTIONARY_FATE_GET_IGNORED = 1,
-
-  // A fetch was attempted, but failed.
-  // TODO(rdsmith): Actually record this case.
-  DICTIONARY_FATE_FETCH_FAILED = 2,
-
-  // A successful fetch was dropped on the floor, no space.
-  DICTIONARY_FATE_FETCH_IGNORED_NO_SPACE = 3,
-
-  // A successful fetch was refused by the SdchManager.
-  DICTIONARY_FATE_FETCH_MANAGER_REFUSED = 4,
-
-  // A dictionary was successfully added based on
-  // a Get-Dictionary header in a response.
-  DICTIONARY_FATE_ADD_RESPONSE_TRIGGERED = 5,
-
-  // A dictionary was evicted by an incoming dict.
-  DICTIONARY_FATE_EVICT_FOR_DICT = 6,
-
-  // A dictionary was evicted by memory pressure.
-  DICTIONARY_FATE_EVICT_FOR_MEMORY = 7,
-
-  // A dictionary was evicted on destruction.
-  DICTIONARY_FATE_EVICT_FOR_DESTRUCTION = 8,
-
-  // A dictionary was successfully added based on
-  // persistence from a previous browser revision.
-  DICTIONARY_FATE_ADD_PERSISTENCE_TRIGGERED = 9,
-
-  // A dictionary was unloaded on destruction, but is still present on disk.
-  DICTIONARY_FATE_UNLOAD_FOR_DESTRUCTION = 10,
-
-  DICTIONARY_FATE_MAX = 11
-};
-
 enum PersistenceFailureReason {
   // File didn't exist; is being created.
   PERSISTENCE_FAILURE_REASON_NO_FILE = 1,
@@ -77,25 +40,11 @@ const int kFreshnessLifetimeHours = 24;
 // Dictionaries that have never been used only stay fresh for one hour.
 const int kNeverUsedFreshnessLifetimeHours = 1;
 
-void RecordDictionaryFate(enum DictionaryFate fate) {
-  UMA_HISTOGRAM_ENUMERATION("Sdch3.DictionaryFate", fate, DICTIONARY_FATE_MAX);
-}
-
 void RecordPersistenceFailure(PersistenceFailureReason failure_reason) {
   UMA_HISTOGRAM_ENUMERATION("Sdch3.PersistenceFailureReason", failure_reason,
                             PERSISTENCE_FAILURE_REASON_MAX);
 }
 
-void RecordDictionaryEvictionOrUnload(int use_count, DictionaryFate fate) {
-  DCHECK(fate == DICTIONARY_FATE_EVICT_FOR_DICT ||
-         fate == DICTIONARY_FATE_EVICT_FOR_MEMORY ||
-         fate == DICTIONARY_FATE_EVICT_FOR_DESTRUCTION ||
-         fate == DICTIONARY_FATE_UNLOAD_FOR_DESTRUCTION);
-
-  UMA_HISTOGRAM_COUNTS_100("Sdch3.DictionaryUseCount", use_count);
-  RecordDictionaryFate(fate);
-}
-
 // Schema specifications and access routines.
 
 // The persistent prefs store is conceptually shared with any other network
@@ -266,6 +215,29 @@ const size_t SdchOwner::kMaxTotalDictionarySize = 20 * 1000 * 1000;
 // amount of space available in storage.
 const size_t SdchOwner::kMinSpaceForDictionaryFetch = 50 * 1000;
 
+void SdchOwner::RecordDictionaryFate(enum DictionaryFate fate) {
+  UMA_HISTOGRAM_ENUMERATION("Sdch3.DictionaryFate", fate, DICTIONARY_FATE_MAX);
+}
+
+void SdchOwner::RecordDictionaryEvictionOrUnload(const std::string& server_hash,
+                                                 size_t size,
+                                                 int use_count,
+                                                 DictionaryFate fate) {
+  DCHECK(fate == DICTIONARY_FATE_EVICT_FOR_DICT ||
+         fate == DICTIONARY_FATE_EVICT_FOR_MEMORY ||
+         fate == DICTIONARY_FATE_EVICT_FOR_DESTRUCTION ||
+         fate == DICTIONARY_FATE_UNLOAD_FOR_DESTRUCTION);
+
+  UMA_HISTOGRAM_COUNTS_100("Sdch3.DictionaryUseCount", use_count);
+  RecordDictionaryFate(fate);
+
+  DCHECK(load_times_.count(server_hash) == 1);
+  base::Time now = clock_->Now();
+  base::TimeDelta dict_lifetime = now - load_times_[server_hash];
+  consumed_byte_seconds_.push_back(size * dict_lifetime.InMilliseconds());
+  load_times_.erase(server_hash);
+}
+
 SdchOwner::SdchOwner(SdchManager* sdch_manager, URLRequestContext* context)
     : manager_(sdch_manager->GetWeakPtr()),
       fetcher_(new SdchDictionaryFetcher(context)),
@@ -285,7 +257,8 @@ SdchOwner::SdchOwner(SdchManager* sdch_manager, URLRequestContext* context)
                      base::Unretained(this))),
       in_memory_pref_store_(new ValueMapPrefStore()),
       external_pref_store_(nullptr),
-      pref_store_(in_memory_pref_store_.get()) {
+      pref_store_(in_memory_pref_store_.get()),
+      creation_time_(clock_->Now()) {
 #if defined(OS_CHROMEOS)
   // For debugging http://crbug.com/454198; remove when resolved.
   CHECK(clock_.get());
@@ -299,7 +272,6 @@ SdchOwner::~SdchOwner() {
   // For debugging http://crbug.com/454198; remove when resolved.
   CHECK_EQ(0u, destroyed_);
   CHECK(clock_.get());
-  clock_.reset();
   CHECK(manager_.get());
 #endif
 
@@ -309,7 +281,8 @@ SdchOwner::~SdchOwner() {
     DictionaryFate fate = IsPersistingDictionaries() ?
                           DICTIONARY_FATE_UNLOAD_FOR_DESTRUCTION :
                           DICTIONARY_FATE_EVICT_FOR_DESTRUCTION;
-    RecordDictionaryEvictionOrUnload(new_uses, fate);
+    RecordDictionaryEvictionOrUnload(it.server_hash(), it.size(), new_uses,
+                                     fate);
   }
   manager_->RemoveObserver(this);
 
@@ -318,6 +291,17 @@ SdchOwner::~SdchOwner() {
   if (external_pref_store_)
     external_pref_store_->RemoveObserver(this);
 
+  int64 object_lifetime =
+      (clock_->Now() - creation_time_).InMilliseconds();
+  for (const auto& val : consumed_byte_seconds_) {
+    if (object_lifetime > 0) {
+      // Objects that are created and immediately destroyed don't add any memory
+      // pressure over time (and also cause a crash here).
+      UMA_HISTOGRAM_MEMORY_KB("Sdch3.TimeWeightedMemoryUse",
+                              val / object_lifetime);
+    }
+  }
+
 #if defined(OS_CHROMEOS)
   destroyed_ = 0xdeadbeef;
 #endif
@@ -450,7 +434,9 @@ void SdchOwner::OnDictionaryFetched(base::Time last_used,
 
     int new_uses = stale_it->use_count -
         use_counts_at_load_[stale_it->server_hash];
-    RecordDictionaryEvictionOrUnload(new_uses,
+    RecordDictionaryEvictionOrUnload(stale_it->server_hash,
+                                     stale_it->dictionary_size,
+                                     new_uses,
                                      DICTIONARY_FATE_EVICT_FOR_DICT);
 
     ++stale_it;
@@ -487,6 +473,7 @@ void SdchOwner::OnDictionaryFetched(base::Time last_used,
   dictionary_description->SetInteger(kDictionarySizeKey,
                                      dictionary_text.size());
   pref_dictionary_map->Set(server_hash, dictionary_description.Pass());
+  load_times_[server_hash] = clock_->Now();
 }
 
 void SdchOwner::OnDictionaryUsed(SdchManager* manager,
@@ -719,7 +706,9 @@ void SdchOwner::OnMemoryPressure(
   for (DictionaryPreferenceIterator it(pref_store_); !it.IsAtEnd();
        it.Advance()) {
     int new_uses = it.use_count() - use_counts_at_load_[it.server_hash()];
-    RecordDictionaryEvictionOrUnload(new_uses,
+    RecordDictionaryEvictionOrUnload(it.server_hash(),
+                                     it.size(),
+                                     new_uses,
                                      DICTIONARY_FATE_EVICT_FOR_MEMORY);
   }