Leaderboard Logging

gm-control can be configured to log a leaderboard of non-2xx requests on a time interval to stdout. This is useful as a quick way to see which endpoints are performing poorly throughout the mesh, without getting into advanced debugging.

Configuration

Leader board logging is configured with two following parameters:

Environment Variable	CLI Flag	Meaning	Type	Example
GM_CONTROL_XDS_GRPC_LOG_TOP_INTERVAL	--xds.grpc-log-top-interval	How often leaderboards are logged and counts reset	Duration	5m3s
GM_CONTROL_XDS_GRPC_LOG_TOP	--xds.grpc-log-top	How many unique requests are logged	integer	5

Leaderboarding can be disabled by setting GM_CONTROL_XDS_GRPC_LOG_TOP to 0.

Schema

Leaderboards are logged to standard out in the format:

[info] <timestamp> ALS: <number of requests>: <HTTP response code> <request path>

Example:

[info] 2020/02/25 20:52:16 ALS: 1: 475 http://localhost:8080/error