Bug 1454100 - Add some telemetry for time spent moving cookies r=Ehsan,francois,mayhemer

MozReview-Commit-ID: 1pAiKaSok3J

--HG--
extra : rebase_source : ac0685003b643dc2ed9b55bfad676dfdddd06e81

netwerk/cookie/CookieServiceChild.cpp

@@ -24,6 +24,8 @@
 #include "nsIPrefService.h"
 #include "nsIPrefBranch.h"
 #include "nsServiceManagerUtils.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/TimeStamp.h"
 
 using namespace mozilla::ipc;
 using mozilla::OriginAttributes;
@@ -114,6 +116,7 @@ CookieServiceChild::CookieServiceChild()
 void
 CookieServiceChild::MoveCookies()
 {
+  TimeStamp start = TimeStamp::Now();
   for (auto iter = mCookiesMap.Iter(); !iter.Done(); iter.Next()) {
     CookiesList *cookiesList = iter.UserData();
     CookiesList newCookiesList;
@@ -135,6 +138,8 @@ CookieServiceChild::MoveCookies()
     }
     cookiesList->SwapElements(newCookiesList);
   }
+
+  Telemetry::AccumulateTimeDelta(Telemetry::COOKIE_TIME_MOVING_MS, start);
 }
 
 NS_IMETHODIMP

toolkit/components/telemetry/Histograms.json

@@ -10228,6 +10228,16 @@
     "n_values": 10,
     "description": "How often are first- and third-party cookies set from HTTPS origins? 0=first/http, 1=first/http+secure?!, 2=first/https, 3=first/https+secure, 4=third/http, 5=third/http+secure?!, 6=third/https, 7=third/https+secure"
   },
+  "COOKIE_TIME_MOVING_MS": {
+    "record_in_processes": ["content"],
+    "alert_emails": ["vgosu@mozilla.com", "necko@mozilla.com"],
+    "bug_numbers": [1454100],
+    "expires_in_version": "64",
+    "kind": "exponential",
+    "high": 3000,
+    "n_buckets": 20,
+    "description": "Time spent moving the cookies from one memory location to another (ms)"
+  },
   "NTLM_MODULE_USED_2": {
     "record_in_processes": ["main", "content"],
     "expires_in_version": "never",