--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -161,16 +161,23 @@
   },
   "MEMORY_RESIDENT": {
     "kind": "exponential",
     "low": "32 * 1024",
     "high": "1024 * 1024",
     "n_buckets": 50,
     "description": "Resident memory size (KB)"
   },
+  "MEMORY_VSIZE": {
+    "kind": "exponential",
+    "low": "32 * 1024",
+    "high": "16 * 1024 * 1024",
+    "n_buckets": 100,
+    "description": "Virtual memory size (KB)"
+  },
   "MEMORY_JS_COMPARTMENTS_SYSTEM": {
     "kind": "exponential",
     "high": "1000",
     "n_buckets": 50,
     "description": "Total JavaScript compartments used for add-ons and internals."
   },
   "MEMORY_JS_COMPARTMENTS_USER": {
     "kind": "exponential",

--- a/toolkit/components/telemetry/TelemetryPing.js
+++ b/toolkit/components/telemetry/TelemetryPing.js
@@ -48,16 +48,17 @@ const RWX_OWNER = 0700;
 //   * MEMORY_JS_COMPARTMENTS_SYSTEM.
 //
 const MEM_HISTOGRAMS = {
   "js-gc-heap": "MEMORY_JS_GC_HEAP",
   "js-compartments/system": "MEMORY_JS_COMPARTMENTS_SYSTEM",
   "js-compartments/user": "MEMORY_JS_COMPARTMENTS_USER",
   "explicit": "MEMORY_EXPLICIT",
   "resident": "MEMORY_RESIDENT",
+  "vsize": "MEMORY_VSIZE",
   "storage-sqlite": "MEMORY_STORAGE_SQLITE",
   "images-content-used-uncompressed":
     "MEMORY_IMAGES_CONTENT_USED_UNCOMPRESSED",
   "heap-allocated": "MEMORY_HEAP_ALLOCATED",
   "heap-committed-unused": "MEMORY_HEAP_COMMITTED_UNUSED",
   "heap-committed-unused-ratio": "MEMORY_HEAP_COMMITTED_UNUSED_RATIO",
   "page-faults-hard": "PAGE_FAULTS_HARD",
   "low-memory-events/virtual": "LOW_MEMORY_EVENTS_VIRTUAL",