Statistics

Currently only the gRPC and file based access logs have statistics.

gRPC access log statistics

The gRPC access log has statistics rooted at access_logs.grpc_access_log. with the following statistics:

Name	Type	Description
logs_written	Counter	Total log entries sent to the logger which were not dropped. This does not imply the logs have been flushed to the gRPC endpoint yet.
logs_dropped	Counter	Total log entries dropped due to network or application level back up.

File access log statistics

The file access log has statistics rooted at the filesystem. namespace.

Name	Type	Description
write_buffered	Counter	Total number of times file data is moved to Envoy’s internal flush buffer
write_completed	Counter	Total number of times a file was successfully written
write_failed	Counter	Total number of times an error occurred during a file write operation
flushed_by_timer	Counter	Total number of times internal flush buffers are written to a file due to flush timeout
reopen_failed	Counter	Total number of times a file was failed to be opened
write_total_buffered	Gauge	Current total size of internal flush buffer in bytes

Fluentd access log statistics

The Fluentd access log has statistics rooted at the access_logs.fluentd.<stat_prefix>. namespace.

Name	Type	Description
entries_lost	Counter	Total number of times an access log entry was discarded due to unavailable connection.
entries_buffered	Counter	Total number of entries (access log record) that was buffered/
events_sent	Counter	Total number of events (Fluentd Forward Mode events) sent to the upstream.
reconnect_attempts	Counter	Total number of times an attempt to reconnect to the upstream has been made.
connections_closed	Counter	Total number of times a connection to the upstream cluster was closed.