September 2025 monthly summary for envoyproxy/envoy: Delivered targeted enhancement to deprecation log handling to improve operator control over log verbosity while preserving visibility for critical warnings. Implemented Deprecation Warning Suppression Control to conditionally suppress deprecation warnings for runtime keys and command-line flags, so warnings are logged only when skip_deprecated_logs is false. This reduces production log noise while maintaining diagnostic access. The work touched core configuration and server initialization (options_impl.cc and server.cc) and was complemented by new unit tests to verify the suppression logic. Commit 520192131714304511243b79da3767c1fe8d50a0a0; PR #40919. Repository: envoyproxy/envoy.

January 2025 performance summary: Delivered two focused enhancements to reduce log noise and improve production observability in Envoy and Istio. Implemented a configurable suppression of deprecated protobuf warnings in envoy, enabling a new CLI flag to control warning logs and aligning proto definitions, validation logic, and CLI parsing. In Istio, added an Envoy log management enhancement with a CLI option to skip deprecated logs, defaulting to skip and allowing override via an environment variable. These changes reduce log verbosity, simplify incident triage, and support safer, configurable deployments. The work reinforces our commitment to maintainability, operator efficiency, and scalable observability across microservices.