Bug 1314378 part A - remove startupcache telemetry of dubious value. r=froydnj

MozReview-Commit-ID: J1cLTvO4ecC

--HG--
extra : rebase_source : f6c504a8279fd2a74e97d544a3812fbb43c93b4d
extra : source : 419e1a311337ecdf208f5474f182d1f88102cc9f

startupcache/StartupCache.cpp

@@ -113,7 +113,6 @@ StartupCache::InitSingleton()
 StaticRefPtr<StartupCache> StartupCache::gStartupCache;
 bool StartupCache::gShutdownInitiated;
 bool StartupCache::gIgnoreDiskCache;
-enum StartupCache::TelemetrifyAge StartupCache::gPostFlushAgeAction = StartupCache::IGNORE_AGE;
 
 NS_IMPL_ISUPPORTS(StartupCache, nsIMemoryReporter)
 
@@ -211,7 +210,7 @@ StartupCache::Init()
                                      false);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  rv = LoadArchive(RECORD_AGE);
+  rv = LoadArchive();
 
   // Sometimes we don't have a cache yet, that's ok.
   // If it's corrupted, just remove it and start over.
@@ -229,7 +228,7 @@ StartupCache::Init()
  * LoadArchive can be called from the main thread or while reloading cache on write thread.
  */
 nsresult
-StartupCache::LoadArchive(enum TelemetrifyAge flag)
+StartupCache::LoadArchive()
 {
   if (gIgnoreDiskCache)
     return NS_ERROR_FAILURE;
@@ -242,32 +241,6 @@ StartupCache::LoadArchive(enum TelemetrifyAge flag)
   
   mArchive = new nsZipArchive();
   rv = mArchive->OpenArchive(mFile);
-  if (NS_FAILED(rv) || flag == IGNORE_AGE)
-    return rv;
-
-  nsCString comment;
-  if (!mArchive->GetComment(comment)) {
-    return rv;
-  }
-
-  const char *data;
-  size_t len = NS_CStringGetData(comment, &data);
-  PRTime creationStamp;
-  // We might not have a comment if the startup cache file was created
-  // before we started recording creation times in the comment.
-  if (len == sizeof(creationStamp)) {
-    memcpy(&creationStamp, data, len);
-    PRTime current = PR_Now();
-    int64_t diff = current - creationStamp;
-
-    // We can't use AccumulateTimeDelta here because we have no way of
-    // reifying a TimeStamp from creationStamp.
-    int64_t usec_per_hour = PR_USEC_PER_SEC * int64_t(3600);
-    int64_t hour_diff = (diff + usec_per_hour - 1) / usec_per_hour;
-    mozilla::Telemetry::Accumulate(Telemetry::STARTUP_CACHE_AGE_HOURS,
-                                   hour_diff);
-  }
-
   return rv;
 }
 
@@ -446,7 +419,7 @@ StartupCache::WriteToDisk()
 
   // If we didn't have an mArchive member, that means that we failed to
   // open the startup cache for reading.  Therefore, we need to record
-  // the time of creation in a zipfile comment; this will be useful for
+  // the time of creation in a zipfile comment; this has been useful for
   // Telemetry statistics.
   PRTime now = PR_Now();
   if (!mArchive) {
@@ -481,7 +454,7 @@ StartupCache::WriteToDisk()
   gIgnoreDiskCache = false;
 
   // Our reader's view of the archive is outdated now, reload it.
-  LoadArchive(gPostFlushAgeAction);
+  LoadArchive();
   
   return;
 }
@@ -497,11 +470,10 @@ StartupCache::InvalidateCache()
   if (NS_FAILED(rv) && rv != NS_ERROR_FILE_TARGET_DOES_NOT_EXIST &&
       rv != NS_ERROR_FILE_NOT_FOUND) {
     gIgnoreDiskCache = true;
-    mozilla::Telemetry::Accumulate(Telemetry::STARTUP_CACHE_INVALID, true);
     return;
   }
   gIgnoreDiskCache = false;
-  LoadArchive(gPostFlushAgeAction);
+  LoadArchive();
 }
 
 void
@@ -623,13 +595,6 @@ StartupCache::ResetStartupWriteTimer()
   return NS_OK;
 }
 
-nsresult
-StartupCache::RecordAgesAlways()
-{
-  gPostFlushAgeAction = RECORD_AGE;
-  return NS_OK;
-}
-
 // StartupCacheDebugOutputStream implementation
 #ifdef DEBUG
 NS_IMPL_ISUPPORTS(StartupCacheDebugOutputStream, nsIObjectOutputStream, 
@@ -819,11 +784,5 @@ StartupCacheWrapper::GetObserver(nsIObserver** obv) {
   return NS_OK;
 }
 
-nsresult
-StartupCacheWrapper::RecordAgesAlways() {
-  StartupCache *sc = StartupCache::GetSingleton();
-  return sc ? sc->RecordAgesAlways() : NS_ERROR_NOT_INITIALIZED;
-}
-
 } // namespace scache
 } // namespace mozilla

startupcache/StartupCache.h

@@ -129,8 +129,6 @@ public:
   nsresult GetDebugObjectOutputStream(nsIObjectOutputStream* aStream,
                                       nsIObjectOutputStream** outStream);
 
-  nsresult RecordAgesAlways();
-
   static StartupCache* GetSingleton();
   static void DeleteSingleton();
 
@@ -144,13 +142,7 @@ private:
   StartupCache();
   virtual ~StartupCache();
 
-  enum TelemetrifyAge {
-    IGNORE_AGE = 0,
-    RECORD_AGE = 1
-  };
-  static enum TelemetrifyAge gPostFlushAgeAction;
-
-  nsresult LoadArchive(enum TelemetrifyAge flag);
+  nsresult LoadArchive();
   nsresult Init();
   void WriteToDisk();
   nsresult ResetStartupWriteTimer();

startupcache/nsIStartupCache.idl

@@ -55,10 +55,6 @@ interface nsIStartupCache : nsISupports
   boolean startupWriteComplete();
   void resetStartupWriteTimer();
 
-  /* Instruct clients to always post cache ages to Telemetry, even in
-     cases where it would not normally make sense.  */
-  void recordAgesAlways();
-
   /* Allows clients to simulate the behavior of ObserverService. */
   readonly attribute nsIObserver observer;
 };

startupcache/test/TestStartupCache.cpp

@@ -410,48 +410,6 @@ int main(int argc, char** argv)
   int rv = 0;
   nsresult scrv;
 
-  // Register TestStartupCacheTelemetry
-  nsCOMPtr<nsIFile> manifest;
-  scrv = NS_GetSpecialDirectory(NS_GRE_DIR,
-                                getter_AddRefs(manifest));
-  if (NS_FAILED(scrv)) {
-    fail("NS_XPCOM_CURRENT_PROCESS_DIR");
-    return 1;
-  }
-
-#ifdef XP_MACOSX
-  nsCOMPtr<nsIFile> tempManifest;
-  manifest->Clone(getter_AddRefs(tempManifest));
-  manifest->AppendNative(
-    NS_LITERAL_CSTRING("TestStartupCacheTelemetry.manifest"));
-  bool exists;
-  manifest->Exists(&exists);
-  if (!exists) {
-    // Workaround for bug 1080338 in mozharness.
-    manifest = tempManifest.forget();
-    manifest->SetNativeLeafName(NS_LITERAL_CSTRING("MacOS"));
-    manifest->AppendNative(
-      NS_LITERAL_CSTRING("TestStartupCacheTelemetry.manifest"));
-  }
-#else
-  manifest->AppendNative(
-    NS_LITERAL_CSTRING("TestStartupCacheTelemetry.manifest"));
-#endif
-
-  XRE_AddManifestLocation(NS_APP_LOCATION, manifest);
-
-  nsCOMPtr<nsIObserver> telemetryThing =
-    do_GetService("@mozilla.org/testing/startup-cache-telemetry.js");
-  if (!telemetryThing) {
-    fail("telemetryThing");
-    return 1;
-  }
-  scrv = telemetryThing->Observe(nullptr, "save-initial", nullptr);
-  if (NS_FAILED(scrv)) {
-    fail("save-initial");
-    rv = 1;
-  }
-
   nsCOMPtr<nsIStartupCache> sc 
     = do_GetService("@mozilla.org/startupcache/cache;1", &scrv);
   if (NS_FAILED(scrv))
@@ -470,11 +428,5 @@ int main(int argc, char** argv)
   if (NS_FAILED(TestEarlyShutdown()))
     rv = 1;
 
-  scrv = telemetryThing->Observe(nullptr, "save-initial", nullptr);
-  if (NS_FAILED(scrv)) {
-    fail("check-final");
-    rv = 1;
-  }
-
   return rv;
 }

startupcache/test/TestStartupCacheTelemetry.js

@@ -1,60 +0,0 @@
-const Cc = Components.classes;
-const Ci = Components.interfaces;
-const Cu = Components.utils;
-
-Cu.import("resource://gre/modules/Services.jsm");
-Cu.import("resource://gre/modules/XPCOMUtils.jsm");
-
-function shouldHaveChanged(a, b)
-{
-  if (a.length != b.length) {
-    throw Error("TEST-UNEXPECTED-FAIL: telemetry count array size changed");
-  }
-
-  for (let i = 0; i < a.length; ++i) {
-    if (a[i] == b[i]) {
-      continue;
-    }
-    return; // something was different, that's all that matters
-  }
-  throw Error("TEST-UNEXPECTED-FAIL: telemetry data didn't change");
-}
-
-function TestStartupCacheTelemetry() { }
-
-TestStartupCacheTelemetry.prototype = {
-  classID: Components.ID("{73cbeffd-d6c7-42f0-aaf3-f176430dcfc8}"),
-  QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver]),
-
-  saveInitial: function() {
-    let t = Services.telemetry;
-    this._age = t.getHistogramById("STARTUP_CACHE_AGE_HOURS").snapshot.counts;
-    this._invalid = t.getHistogramById("STARTUP_CACHE_INVALID").snapshot.counts;
-  },
-
-  checkFinal: function() {
-    let t = Services.telemetry;
-    let newAge = t.getHistogramById("STARTUP_CACHE_AGE_HOURS").snapshot.counts;
-    shouldHaveChanged(this._age, newAge);
-
-    let newInvalid = t.getHistogramById("STARTUP_CACHE_INVALID").snapshot.counts;
-    shouldHaveChanged(this._invalid, newInvalid);
-  },
-
-  observe: function(subject, topic, data) {
-    switch (topic) {
-    case "save-initial":
-      this.saveInitial();
-      break;
-
-    case "check-final":
-      this.checkFinal();
-      break;
-
-    default:
-      throw Error("BADDOG, NO MILKBONE FOR YOU");
-    }
-  },
-};
-
-this.NSGetFactory = XPCOMUtils.generateNSGetFactory([TestStartupCacheTelemetry]);

startupcache/test/TestStartupCacheTelemetry.manifest

@@ -1,2 +0,0 @@
-component {73cbeffd-d6c7-42f0-aaf3-f176430dcfc8} TestStartupCacheTelemetry.js
-contract @mozilla.org/testing/startup-cache-telemetry.js {73cbeffd-d6c7-42f0-aaf3-f176430dcfc8}

startupcache/test/moz.build

@@ -7,8 +7,3 @@
 GeckoCppUnitTests([
     'TestStartupCache',
 ])
-
-EXTRA_COMPONENTS += [
-    'TestStartupCacheTelemetry.js',
-    'TestStartupCacheTelemetry.manifest',
-]

toolkit/components/telemetry/Histograms.json

@@ -1238,19 +1238,6 @@
     "n_buckets": 20,
     "description": "Maximum retention time for the gradient cache. (ms)"
   },
-  "STARTUP_CACHE_AGE_HOURS": {
-    "expires_in_version": "default",
-    "kind": "exponential",
-    "high": 3000,
-    "n_buckets": 20,
-    "description": "Startup cache age (hours)"
-  },
-  "STARTUP_CACHE_INVALID": {
-    "alert_emails": ["perf-telemetry-alerts@mozilla.com"],
-    "expires_in_version": "never",
-    "kind": "flag",
-    "description": "Was the disk startup cache file detected as invalid"
-  },
   "WORD_CACHE_HITS_CONTENT": {
     "expires_in_version": "never",
     "kind": "exponential",

toolkit/components/telemetry/histogram-whitelists.json

@@ -637,9 +637,8 @@
     "SPDY_SYN_REPLY_RATIO",
     "SPDY_SYN_REPLY_SIZE",
     "SPDY_SYN_SIZE",
-    "SPDY_VERSION2",
-    "STARTUP_CACHE_AGE_HOURS",
     "STARTUP_CRASH_DETECTED",
+    "SPDY_VERSION2",
     "STARTUP_MEASUREMENT_ERRORS",
     "STS_NUMBER_OF_ONSOCKETREADY_CALLS",
     "STS_NUMBER_OF_PENDING_EVENTS",
@@ -1569,8 +1568,6 @@
     "SSL_TLS12_INTOLERANCE_REASON_PRE",
     "SSL_VERSION_FALLBACK_INAPPROPRIATE",
     "SSL_WEAK_CIPHERS_FALLBACK",
-    "STARTUP_CACHE_AGE_HOURS",
-    "STARTUP_CACHE_INVALID",
     "STARTUP_CRASH_DETECTED",
     "STARTUP_MEASUREMENT_ERRORS",
     "STS_NUMBER_OF_ONSOCKETREADY_CALLS",
@@ -1953,7 +1950,6 @@
     "FX_SESSION_RESTORE_AUTO_RESTORE_DURATION_UNTIL_EAGER_TABS_RESTORED_MS",
     "FX_SESSION_RESTORE_COLLECT_DATA_MS",
     "FX_SESSION_RESTORE_FILE_SIZE_BYTES",
-    "STARTUP_CACHE_AGE_HOURS",
     "FX_SESSION_RESTORE_DOM_STORAGE_SIZE_ESTIMATE_CHARS",
     "DATA_STORAGE_ENTRIES",
     "TRANSLATED_PAGES_BY_LANGUAGE",