Prometheus Metrics

ProxySQL exposes application metrics via the /metrics endpoint in Prometheus exposition format. This page is a complete reference of all metrics available in ProxySQL v3.0, organized by functional area.

For setup and configuration of the Prometheus exporter, see Prometheus Exporter.

Metrics Categories

1. Query Processing
2. Connection Management
3. Connection Pool (Per-Server)
4. Error Tracking
5. Backend Monitoring
6. Query Cache
7. Query Logging
8. Server Status
9. System & Memory
10. Cluster
11. Debug

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Query Processing

Metrics tracking query execution: bytes transferred between frontends and backends, query processing time, query counts, and connection pool acquisition statistics.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_queries_backends_bytes_total	Counter	Bytes sent/received to backends	✅	❌	protocol: mysql traffic_flow: sent, received
proxysql_queries_frontends_bytes_total	Counter	Bytes sent/received from frontends	✅	❌	protocol: mysql traffic_flow: sent, received
proxysql_query_processor_time_seconds_total	Counter	Time spent in query processor	✅	❌	protocol: mysql
proxysql_backend_query_time_seconds_total	Counter	Time spent in backend network calls	✅	❌	protocol: mysql
proxysql_com_backend_stmt_total	Counter	Backend prepared statement operations	✅	❌	protocol: mysql op: prepare, execute, close
proxysql_com_frontend_stmt_total	Counter	Frontend prepared statement operations	✅	❌	protocol: mysql op: prepare, execute, close
proxysql_questions_total	Counter	Total client queries executed	✅	❌	protocol: mysql
proxysql_slow_queries_total	Counter	Queries exceeding long_query_time	✅	❌	protocol: mysql
proxysql_gtid_consistent_queries_total	Counter	GTID consistent reads	✅	❌	protocol: mysql
proxysql_gtid_session_collected_total	Counter	GTID session state queries	✅	❌	protocol: mysql
proxysql_connpool_get_conn_success_latency_awareness_total	Counter	Latency-aware connection picks	✅	❌	protocol: mysql
proxysql_connpool_get_conn_success_immediate_total	Counter	Per-thread connection cache hits	✅	❌	protocol: mysql
proxysql_connpool_get_conn_success_total	Counter	Successful connection pool gets	✅	❌	protocol: mysql
proxysql_connpool_get_conn_failure_total	Counter	Failed connection pool gets	✅	❌	protocol: mysql
proxysql_generated_error_packets_total	Counter	Error packets generated by ProxySQL	✅	❌	protocol: mysql
proxysql_max_connect_timeouts_total	Counter	Backend connect timeouts	✅	❌	protocol: mysql
proxysql_backend_lagging_during_query_total	Counter	Queries failed due to server lag	✅	❌	protocol: mysql
proxysql_backend_offline_during_query_total	Counter	Queries failed due to server offline	✅	❌	protocol: mysql
proxysql_queries_with_max_lag_total	Counter	Queries with max_lag attribute	✅	❌	protocol: mysql
proxysql_queries_with_max_lag__delayed_total	Counter	Queries delayed by max_lag	✅	❌	protocol: mysql
proxysql_queries_with_max_lag__total_wait_time_total	Counter	Total wait time due to max_lag delays	✅	❌	protocol: mysql
proxysql_mysql_unexpected_frontend_com_quit_total	Counter	Unexpected COM_QUIT from clients	✅	❌	protocol: mysql
proxysql_hostgroup_locked_set_cmds_total	Counter	Connections locked into a hostgroup	✅	❌	protocol: mysql
proxysql_hostgroup_locked_queries_total	Counter	Queries on hostgroup-locked connections	✅	❌	protocol: mysql
proxysql_mysql_unexpected_frontend_packets_total	Counter	Unexpected packets from clients	✅	❌	protocol: mysql
proxysql_aws_aurora_replicas_skipped_during_query_total	Counter	Aurora replicas skipped due to lag	✅	❌	protocol: mysql
proxysql_automatic_detected_sql_injection_total	Counter	SQL injection attempts blocked	✅	❌	protocol: mysql
proxysql_mysql_whitelisted_sqli_fingerprint_total	Counter	Whitelisted SQL injection fingerprints	✅	❌	protocol: mysql
proxysql_mysql_killed_backend_connections_total	Counter	Killed backend connections	✅	❌	protocol: mysql
proxysql_mysql_killed_backend_queries_total	Counter	Killed backend queries	✅	❌	protocol: mysql
proxysql_client_host_error_killed_connections	Counter	Connections killed by host error limit	✅	❌	protocol: mysql
proxysql_mysql_unexpected_frontend_com_ping_total	Counter	Unexpected COM_PING from clients	✅	❌	—
proxysql_ai_detected_anomalies_total	Counter	AI-detected query anomalies	✅	❌	protocol: mysql
proxysql_ai_blocked_queries_total	Counter	Queries blocked by AI detection	✅	❌	protocol: mysql
proxysql_mysql_set_wait_timeout_commands_total	Counter	SET wait_timeout commands received	✅	❌	—
proxysql_mysql_timeout_terminated_connections_total	Counter	Connections terminated by wait_timeout	✅	❌	—

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Connection Management

Metrics for connection lifecycle events: creation, authentication, transaction commands, and protocol-specific connection operations such as SET NAMES, INIT DB, and SET client_encoding.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_servers_table_version_total	Counter	Server table version changes	✅	✅	—
proxysql_server_connections_total	Counter	Server connections by status	✅	✅	protocol: mysql, pgsql status: created, delayed, aborted
proxysql_client_connections_total	Counter	Client connections by status	✅	✅	protocol: mysql, pgsql status: created, aborted
proxysql_client_connections_sha2cached_total	Counter	SHA2 cached password authentication attempts	✅	❌	—
proxysql_com_autocommit_total	Counter	Autocommitted queries	✅	❌	—
proxysql_com_autocommit_filtered_total	Counter	Filtered autocommit commands	✅	❌	—
proxysql_com_rollback_total	Counter	Transaction rollbacks	✅	✅	—
proxysql_com_rollback_filtered_total	Counter	Filtered rollback commands	✅	✅	—
proxysql_com_backend_change_user_total	Counter	Backend COM_CHANGE_USER commands	✅	❌	—
proxysql_com_backend_init_db_total	Counter	Backend INIT DB commands	✅	❌	—
proxysql_com_backend_set_names_total	Counter	Backend SET NAMES commands	✅	❌	—
proxysql_com_frontend_init_db_total	Counter	Frontend INIT DB commands	✅	❌	—
proxysql_com_frontend_set_names_total	Counter	Frontend SET NAMES commands	✅	❌	—
proxysql_com_frontend_use_db_total	Counter	Frontend USE DB commands	✅	❌	—
proxysql_com_backend_reset_connection_total	Counter	Backend reset connection commands	❌	✅	—
proxysql_com_backend_set_client_encoding_total	Counter	Backend SET client_encoding commands	❌	✅	—
proxysql_com_frontend_set_client_encoding_total	Counter	Frontend SET client_encoding commands	❌	✅	—
proxysql_com_commit_cnt_total	Counter	Transaction commits	✅	✅	—
proxysql_com_commit_cnt_filtered_total	Counter	Filtered commit commands	✅	✅	—
proxysql_selects_for_update__autocommit0_total	Counter	SELECT FOR UPDATE with autocommit off	✅	✅	—
proxysql_myhgm_myconnpool_get_total	Counter	MySQL connection pool requests	✅	❌	—
proxysql_myhgm_myconnpool_get_ok_total	Counter	MySQL connection pool successes	✅	❌	—
proxysql_myhgm_myconnpool_get_ping_total	Counter	MySQL connection pool ping keep-alives	✅	❌	—
proxysql_myhgm_myconnpool_push_total	Counter	MySQL connection pool returns	✅	❌	—
proxysql_myhgm_myconnpool_reset_total	Counter	MySQL connection pool resets	✅	❌	—
proxysql_myhgm_myconnpool_destroy_total	Counter	MySQL connection pool destroys	✅	❌	—
proxysql_myhgm_auto_increment_multiplex_total	Counter	Auto-increment multiplex triggers	✅	✅	—
proxysql_pghgm_pgconnpool_get_total	Counter	PostgreSQL connection pool requests	❌	✅	—
proxysql_pghgm_pgconnpool_get_ok_total	Counter	PostgreSQL connection pool successes	❌	✅	—
proxysql_pghgm_myconnpool_get_ping_total	Counter	PostgreSQL connection pool ping keep-alives	❌	✅	—
proxysql_pghgm_pgconnpool_push_total	Counter	PostgreSQL connection pool returns	❌	✅	—
proxysql_pghgm_pgconnpool_reset_total	Counter	PostgreSQL connection pool resets	❌	✅	—
proxysql_pghgm_pgconnpool_destroy_total	Counter	PostgreSQL connection pool destroys	❌	✅	—

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Connection Pool (Per-Server)

Per-backend server metrics with dynamic labels for hostgroup and endpoint. The number of time series scales with the number of configured backend servers.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_connpool_data_bytes_total	Counter	Bytes sent/received to backend servers	✅	✅	hostgroup, endpoint traffic_flow: sent, recv
proxysql_connpool_conns_total	Counter	Connection attempts to backend servers	✅	✅	hostgroup, endpoint status: ok, err
proxysql_connpool_conns_queries_total	Counter	Queries routed to backend servers	✅	✅	hostgroup, endpoint
proxysql_gtid_executed_total	Counter	GTID executions per backend server	✅	✅	hostgroup, endpoint
proxysql_connpool_conns	Gauge	Backend connections by status	✅	✅	hostgroup, endpoint status: free, used
proxysql_connpool_conns_latency_us	Gauge	Backend server ping latency (microseconds)	✅	✅	hostgroup, endpoint
proxysql_connpool_conns_status	Gauge	Backend server status (1=ONLINE, 2=SHUNNED, 3=OFFLINE_SOFT, 4=OFFLINE_HARD, 5=SHUNNED_REPL_LAG)	✅	✅	hostgroup, endpoint

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Error Tracking

Error counters for authentication denials and backend/proxy-generated errors. Error metrics use dynamic labels and can produce a large number of time series.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_access_denied_wrong_password_total	Counter	Wrong password denials	✅	✅	protocol: mysql, pgsql
proxysql_access_denied_max_connections_total	Counter	Max connections denials	✅	✅	protocol: mysql, pgsql
proxysql_access_denied_max_user_connections_total	Counter	Max user connections denials	✅	✅	protocol: mysql, pgsql
proxysql_mysql_error_total	Counter	MySQL errors generated by ProxySQL	✅	❌	hostgroup, endpoint, errno
mysql_error_total	Counter	MySQL errors from backends	✅	❌	hostgroup, endpoint, errno
proxysql_pgsql_error_total	Counter	PostgreSQL errors generated by ProxySQL	❌	✅	hostgroup, endpoint, errno
pgsql_error_total	Counter	PostgreSQL errors from backends	❌	✅	hostgroup, endpoint, errno

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Backend Monitoring

Health check metrics from ProxySQL's MySQL backend monitoring system: connect checks, ping checks, read-only checks, replication lag checks, and DNS cache statistics.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_mysql_monitor_workers_started_total	Counter	Monitor worker threads started	✅	❌	—
proxysql_mysql_monitor_connect_check_total	Counter	Backend connect checks	✅	❌	status: ok, err
proxysql_mysql_monitor_ping_check_total	Counter	Backend ping checks	✅	❌	status: ok, err
proxysql_mysql_monitor_read_only_check_total	Counter	Backend read-only checks	✅	❌	status: ok, err
proxysql_mysql_monitor_replication_lag_check_total	Counter	Backend replication lag checks	✅	❌	status: ok, err
proxysql_mysql_monitor_dns_cache_queried	Counter	DNS cache queries	✅	❌	—
proxysql_mysql_monitor_dns_cache_lookup_success	Counter	DNS cache successful lookups	✅	❌	—
proxysql_mysql_monitor_dns_cache_record_updated	Counter	DNS cache records updated	✅	❌	—
proxysql_mysql_monitor_workers	Gauge	Current monitor worker threads	✅	❌	—
proxysql_mysql_monitor_workers_aux	Gauge	Current auxiliary monitor threads	✅	❌	—

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Query Cache

ProxySQL's built-in query cache metrics: cache hit/miss rates, byte throughput, entry counts, and memory usage.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_query_cache_count_get_total	Counter	Cache read requests	✅	✅	protocol: mysql, pgsql status: ok, err
proxysql_query_cache_count_set_total	Counter	Cache write requests	✅	✅	protocol: mysql, pgsql
proxysql_query_cache_bytes_total	Counter	Cache bytes read/written	✅	✅	protocol: mysql, pgsql op: read, written
proxysql_query_cache_purged_total	Counter	Cache entries purged by TTL	✅	✅	protocol: mysql, pgsql
proxysql_query_cache_entries_total	Counter	Current number of cache entries	✅	✅	protocol: mysql, pgsql
proxysql_query_cache_memory_bytes	Gauge	Current cache memory usage	✅	✅	protocol: mysql, pgsql

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Query Logging

Metrics from ProxySQL's query logging subsystem: event copying to memory and disk, event retrieval, circular buffer status, and total logged queries.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_mysql_logger_copy_total	Counter	MySQL logger copy operations	✅	❌	target: memory, disk
proxysql_mysql_logger_get_all_events_calls_total	Counter	MySQL logger get_all_events calls	✅	❌	—
proxysql_mysql_logger_get_all_events_events_total	Counter	MySQL logger events retrieved	✅	❌	—
proxysql_mysql_logger_copy_seconds_total	Counter	MySQL logger copy duration	✅	❌	target: memory, disk
proxysql_mysql_logger_get_all_events_seconds_total	Counter	MySQL logger get_all_events duration	✅	❌	—
proxysql_mysql_logger_events_copied_total	Counter	MySQL logger events copied	✅	❌	target: memory, disk
proxysql_mysql_logger_circular_buffer_events_total	Counter	MySQL logger buffer events	✅	❌	type: added, dropped
proxysql_mysql_logger_circular_buffer_events	Gauge	MySQL logger current buffer size	✅	❌	—
proxysql_pgsql_logger_copy_total	Counter	PostgreSQL logger copy operations	❌	✅	target: memory, disk
proxysql_pgsql_logger_get_all_events_calls_total	Counter	PostgreSQL logger get_all_events calls	❌	✅	—
proxysql_pgsql_logger_get_all_events_events_total	Counter	PostgreSQL logger events retrieved	❌	✅	—
proxysql_pgsql_logger_copy_seconds_total	Counter	PostgreSQL logger copy duration	❌	✅	target: memory, disk
proxysql_pgsql_logger_get_all_events_seconds_total	Counter	PostgreSQL logger get_all_events duration	❌	✅	—
proxysql_pgsql_logger_events_copied_total	Counter	PostgreSQL logger events copied	❌	✅	target: memory, disk
proxysql_pgsql_logger_circular_buffer_events_total	Counter	PostgreSQL logger buffer events	❌	✅	type: added, dropped
proxysql_pgsql_logger_circular_buffer_events	Gauge	PostgreSQL logger current buffer size	❌	✅	—
proxysql_query_logger_logged_queries_total	Counter	Total queries accepted by query loggers	✅	✅	protocol: mysql, pgsql

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Server Status

Point-in-time gauges for active transactions, connection states, buffer memory, query mirroring, thread worker counts, monitor configuration, and current connected clients and servers.

Metric	Type	Description	MySQL	PostgreSQL	Labels
proxysql_active_transactions	Gauge	Current transactions in progress	✅	❌	protocol: mysql
proxysql_client_connections_non_idle	Gauge	Non-idle client connections	✅	❌	protocol: mysql
proxysql_client_connections_hostgroup_locked	Gauge	Hostgroup-locked connections	✅	❌	protocol: mysql
proxysql_mysql_backend_buffers_bytes	Gauge	Backend fast_forward buffer memory	✅	❌	—
proxysql_mysql_frontend_buffers_bytes	Gauge	Frontend buffer memory	✅	❌	—
proxysql_mysql_session_internal_bytes	Gauge	Session internal memory	✅	❌	—
proxysql_mirror_concurrency	Gauge	Active mirror sessions	✅	❌	protocol: mysql
proxysql_mirror_queue_lengths	Gauge	Queued mirror sessions	✅	❌	protocol: mysql
proxysql_mysql_thread_workers	Gauge	MySQL thread worker count	✅	❌	—
proxysql_mysql_wait_timeout	Gauge	Session idle timeout (seconds)	✅	❌	—
proxysql_mysql_max_connections	Gauge	Maximum client connections	✅	❌	—
proxysql_mysql_monitor_enabled	Gauge	Monitor enabled (1=yes, 0=no)	✅	❌	—
proxysql_mysql_monitor_ping_interval	Gauge	Monitor ping interval (ms)	✅	❌	—
proxysql_mysql_monitor_ping_timeout_seconds	Gauge	Monitor ping timeout	✅	❌	—
proxysql_mysql_monitor_ping_max_failures	Gauge	Monitor ping max failures before shunning	✅	❌	—
proxysql_mysql_monitor_aws_rds_topology_discovery_interval	Gauge	AWS RDS topology discovery interval (ms)	✅	❌	—
proxysql_mysql_monitor_read_only_interval_seconds	Gauge	Monitor read-only check interval	✅	❌	—
proxysql_mysql_monitor_read_only_timeout_seconds	Gauge	Monitor read-only check timeout	✅	❌	—
proxysql_mysql_monitor_writer_is_also_reader	Gauge	Writer-is-also-reader mode	✅	❌	—
proxysql_monitor_replication_lag_group_by_host	Gauge	Replication lag group-by-host mode	✅	❌	—
proxysql_mysql_monitor_replication_lag_interval_seconds	Gauge	Replication lag check interval	✅	❌	—
proxysql_mysql_monitor_replication_lag_timeout_seconds	Gauge	Replication lag check timeout	✅	❌	—
proxysql_mysql_monitor_history_timeout_seconds	Gauge	Monitor event history retention	✅	❌	—
proxysql_server_connections_connected	Gauge	Current backend connections	✅	✅	protocol: mysql, pgsql
proxysql_client_connections_connected	Gauge	Current client connections	✅	✅	protocol: mysql, pgsql
proxysql_client_connections_connected_primary	Gauge	Connections using primary password	✅	❌	—
proxysql_client_connections_connected_additional	Gauge	Connections using additional password	✅	❌	—

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System & Memory

ProxySQL process-level metrics: uptime, memory allocators, prepared statement caches, firewall memory, stack sizes, file descriptors, and version information. These metrics are protocol-independent.

Metric	Type	Description	Labels
proxysql_uptime_seconds_total	Counter	ProxySQL uptime in seconds	—
proxysql_jemalloc_allocated_bytes_total	Counter	Bytes allocated by the application	—
proxysql_mysql_listener_paused	Gauge	MySQL listener paused (1=paused, 0=active)	—
proxysql_pgsql_listener_paused	Gauge	PostgreSQL listener paused (1=paused, 0=active)	—
proxysql_connpool_memory_bytes	Gauge	Connection pool metadata memory	—
proxysql_sqlite3_memory_bytes	Gauge	SQLite memory usage	—
proxysql_jemalloc_bytes	Gauge	Jemalloc memory statistics	type: resident, active, mapped, metadata, retained
proxysql_query_digest_memory_bytes	Gauge	Query digest memory	—
proxysql_auth_memory_bytes	Gauge	Authentication module memory	—
proxysql_mysql_query_rules_memory_bytes	Gauge	Query rules memory	—
proxysql_mysql_firewall_users_table_bytes	Gauge	Firewall users table memory	—
proxysql_mysql_firewall_users_config_bytes	Gauge	Firewall users config memory	—
proxysql_mysql_firewall_rules_table_bytes	Gauge	Firewall rules table memory	—
proxysql_mysql_firewall_rules_config_bytes	Gauge	Firewall rules config memory	—
proxysql_stack_memory_mysql_threads_bytes	Gauge	MySQL thread stack memory	—
proxysql_stack_memory_admin_threads_bytes	Gauge	Admin thread stack memory	—
proxysql_stack_memory_cluster_threads	Gauge	Cluster thread stack memory	—
proxysql_stmt_client_active	Gauge	Active client prepared statements	—
proxysql_stmt_client_active_unique	Gauge	Unique active client prepared statements	—
proxysql_stmt_server_active	Gauge	Active server prepared statements	—
proxysql_stmt_server_active_unique	Gauge	Unique active server prepared statements	—
proxysql_stmt_max_stmt_id	Gauge	Maximum statement ID ever used	—
proxysql_stmt_cached	Gauge	Cached global prepared statements with metadata	—
prepare_stmt_metadata_memory_bytes	Gauge	Prepared statement metadata memory	—
prepare_stmt_backend_memory_bytes	Gauge	Prepared statement backend memory	—
proxysql_fds_in_use	Gauge	File descriptors in use	—
proxysql_version_info	Gauge	ProxySQL version information (always 1)	version, version_comment

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Cluster

ProxySQL Cluster synchronization metrics: configuration pulls from peers, sync conflicts, node checksums, and peer health statistics. Labels include hostname and port for per-node metrics.

Metric	Type	Description	Labels
proxysql_cluster_pulled_total	Counter	Configuration pulls from cluster peers	module_name: mysql_query_rules, mysql_servers, mysql_servers_replication_hostgroups, mysql_servers_group_replication_hostgroups, mysql_servers_galera_hostgroups, mysql_servers_aws_aurora_hostgroups, mysql_servers_hostgroup_attributes, mysql_servers_ssl_params, mysql_servers_runtime_checks, mysql_users, proxysql_servers, mysql_variables, admin_variables, ldap_variables, mysql_ldap_mapping status: success, failure
proxysql_cluster_syn_conflict_total	Counter	Cluster synchronization conflicts	module_name: mysql_query_rules, mysql_servers, mysql_users, proxysql_servers, mysql_variables, admin_variables, ldap_variables reason: servers_share_epoch, version_one
proxysql_servers_checksums_version_total	Counter	Configuration load count per node	hostname, port, name
proxysql_servers_metrics_uptime_s_total	Counter	Cluster node uptime	hostname, port
proxysql_servers_metrics_queries_total	Counter	Queries processed by cluster node	hostname, port
proxysql_servers_metrics_client_conns_created_total	Counter	Client connections created on cluster node	hostname, port
proxysql_servers_clients_status_last_seen_at	Gauge	Last time a cluster node was seen	hostname, port
proxysql_servers_checksums_epoch	Gauge	Configuration creation timestamp	hostname, port, name
proxysql_servers_checksums_changed_at	Gauge	Configuration load timestamp	hostname, port, name
proxysql_servers_checksums_updated_at	Gauge	Last checksum verification timestamp	hostname, port, name
proxysql_servers_checksums_diff_check	Gauge	Consecutive checksum diff detections	hostname, port, name
proxysql_servers_metrics_weight	Gauge	Cluster node weight	hostname, port
proxysql_servers_metrics_response_time_ms	Gauge	Cluster check response time (ms)	hostname, port
proxysql_servers_metrics_last_check_ms	Gauge	Cluster check processing time (ms)	hostname, port
proxysql_servers_metrics_client_conns_connected_total	Gauge	Current frontend connections on cluster node	hostname, port

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Debug

Internal debug message counters. A new time series is created for each unique combination of message ID, source file, line number, and function name.

Metric	Type	Description	Labels
proxysql_message_count_total	Counter	Number of times a debug message has been logged	message_id, filename, line, func