tor-browser

commit 898aa6ef1ce8a2739a0d0a9b489014a3e11cca7d
parent bb807f8739cf89969f3d9a0e042935b853a95f16
Author: Oskar Mansfeld <git@omansfeld.net>
Date:   Tue, 16 Dec 2025 14:54:02 +0000

Bug 2004717 - Add glean probe counting whether an HTTP3 connection exited slow start. r=mxinden,necko-reviewers,valentin

Differential Revision: https://phabricator.services.mozilla.com/D275481

Diffstat:
M
netwerk/metrics.yaml
 | 
18
++++++++++++++++++
M
netwerk/socket/neqo_glue/src/lib.rs
 | 
12
++++++++++--

2 files changed, 28 insertions(+), 2 deletions(-)
diff --git a/netwerk/metrics.yaml b/netwerk/metrics.yaml
@@ -1113,6 +1113,24 @@ networking:
       - omansfeld@mozilla.com
     expires: 157
 
+  http_3_slow_start_exited:
+    type: labeled_counter
+    description: >
+      Counts whether an HTTP3 connections exited slow start.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=2004717
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=2004717
+    data_sensitivity:
+      - technical
+    notification_emails:
+      - necko@mozilla.com
+      - omansfeld@mozilla.com
+    expires: 157
+    labels:
+      - exited
+      - not_exited
+
   http_3_connection_close_reason:
     type: labeled_counter
     description: >
diff --git a/netwerk/socket/neqo_glue/src/lib.rs b/netwerk/socket/neqo_glue/src/lib.rs
@@ -672,8 +672,9 @@ impl NeqoHttp3Conn {
             }
         }
 
-        // Ignore connections into the void.
+        // Ignore connections into the void for metrics where it makes sense.
         if stats.packets_rx != 0 {
+            // Calculate and collect packet loss ratio.
             if let Ok(loss) =
                 i64::try_from((stats.lost * PRECISION_FACTOR_USIZE) / stats.packets_tx)
             {
@@ -683,9 +684,16 @@ impl NeqoHttp3Conn {
                 qwarn!("{msg}");
                 debug_assert!(false, "{msg}");
             }
+
+            // Count whether the connection exited slow start.
+            if stats.cc.slow_start_exited {
+                glean::http_3_slow_start_exited.get("exited").add(1);
+            } else {
+                glean::http_3_slow_start_exited.get("not_exited").add(1);
+            }
         }
 
-        // Ignore connections that never had loss induced congestion events (and prevent dividing by zero)
+        // Ignore connections that never had loss induced congestion events (and prevent dividing by zero).
         if stats.cc.congestion_events_loss != 0 {
             if let Ok(spurious) = i64::try_from(
                 (stats.cc.congestion_events_spurious * PRECISION_FACTOR_USIZE)