quic: upstream connections read 32 packets per loop (#32693)

Commit Message: change the current behavior from reading up to 16 * number of in-flight requests to reading 32 packets per-connection. Risk Level: low, HTTP/3 upstream is in Alpha now Testing: existing tests pass Docs Changes: N/A Release Notes: Yes Platform Specific Features: N/A Runtime guard: envoy.reloadable_features.quic_upstream_reads_fixed_number_packets Signed-off-by: Dan Zhang <[email protected]>
envoyproxy · Mar 5, 2024 · 9e683d2 · 9e683d2
1 parent 8003a96
commit 9e683d2
Show file tree

Hide file tree

Showing 3 changed files with 8 additions and 1 deletion.
diff --git a/changelogs/current.yaml b/changelogs/current.yaml
@@ -51,6 +51,10 @@ minor_behavior_changes:
     Port migration is default turned off. QUIC client connections will no longer attempt to migrate to a new port when connections
     is degrading. Can be manually turned on via
     :ref:`port_migration <envoy_v3_api_field_config.core.v3.QuicProtocolOptions.num_timeouts_to_trigger_port_migration>`.
+- area: QUIC
+  change: |
+    Make each upstream connection to read as many as 32 packets in each event loop. This feature can be disabled by setting
+    ``envoy.reloadable_features.quic_upstream_reads_fixed_number_packets`` to false.
 - area: aws
   change: |
     AWS region string is now retrieved from environment and profile consistently within aws_request_signer and

diff --git a/source/common/quic/envoy_quic_client_connection.h b/source/common/quic/envoy_quic_client_connection.h
@@ -80,7 +80,9 @@ class EnvoyQuicClientConnection : public quic::QuicConnection,
     // TODO(mattklein123): Emit a stat for this.
   }
   size_t numPacketsExpectedPerEventLoop() const override {
-    if (delegate_.has_value()) {
+    if (!Runtime::runtimeFeatureEnabled(
+            "envoy.reloadable_features.quic_upstream_reads_fixed_number_packets") &&
+        delegate_.has_value()) {
       return delegate_->numPacketsExpectedPerEventLoop();
     }
     return DEFAULT_PACKETS_TO_READ_PER_CONNECTION;

diff --git a/source/common/runtime/runtime_features.cc b/source/common/runtime/runtime_features.cc
@@ -81,6 +81,7 @@ RUNTIME_GUARD(envoy_reloadable_features_quic_fix_filter_manager_uaf);
 // Ignore the automated "remove this flag" issue: we should keep this for 1 year. Confirm with
 // @danzh2010 or @RyanTheOptimist before removing.
 RUNTIME_GUARD(envoy_reloadable_features_quic_send_server_preferred_address_to_all_clients);
+RUNTIME_GUARD(envoy_reloadable_features_quic_upstream_reads_fixed_number_packets);
 RUNTIME_GUARD(envoy_reloadable_features_sanitize_te);
 RUNTIME_GUARD(envoy_reloadable_features_send_header_raw_value);
 RUNTIME_GUARD(envoy_reloadable_features_send_local_reply_when_no_buffer_and_upstream_request);