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Co-authored-by: djshow832 <[email protected]>

tiproxy/tiproxy-grafana.md

@@ -21,27 +21,42 @@ TiProxy has four panel groups. The metrics on these panels indicate the current
 
 ## Server
 
-- CPU Usage: The CPU utilization per TiProxy instance.
-- Memory Usage: The memory usage per TiProxy instance.
-- Uptime: The runtime of TiProxy since last restart.
-- Goroutine Count: Running goroutine count of TiProxy instance.
-- Connection Count: SQL connections that TiProxy instance serve.
+- CPU Usage: the CPU utilization of each TiProxy instance
+- Memory Usage: the memory usage of each TiProxy instance
+- Uptime: the runtime of each TiProxy instance since last restart
+- Connection Count: the number of clients connected to each TiProxy instance
+- Create Connection OPM: the number of creating connections on each TiProxy instance every minute
+- Disconnection OPM: the number of disconnections for each reason every minute. Reasons include:
+  - success: the client disconnects normally
+  - client network break: the client does not send a `QUIT` command before it disconnects. It may also be caused by a network problem or the client shutting down
+  - client handshake fail: the client fails to handshake with TiProxy
+  - auth fail: the access is denied by TiDB
+  - SQL error: TiDB returns other SQL errors
+  - proxy shutdown: TiProxy is shutting down
+  - malformed packet: TiProxy fails to parse the MySQL packet
+  - get backend fail: TiProxy fails to find an available backend for the connection
+  - proxy error: other TiProxy errors
+  - backend network break: fails to read from or write to the TiDB. This may be caused by a network problem or the TiDB server shutting down
+  - backend handshake fail: TiProxy fails to handshake with the TiDB server
+- Goroutine Count: the number of Goroutines on each TiProxy instance
 
 ## Query-Summary
 
-- Duration: average, p95, p99 SQL statement execution duration.
-- CPS by Instance: command per second of all TiProxy instances.
-- CPS by Backend: command per second of all TiDB instances.
-- CPS by CMD: command per second grouped by SQL command type.
+- Duration: average, p95, p99 SQL statement execution duration. It includes the duration of SQL statement execution on TiDB servers, so it is higher than the duration on the TiDB Grafana panel
+- P99 Duration By Instance: p99 statement execution duration of each TiProxy instance
+- P99 Duration By Backend: p99 statement execution duration of the statements that are executed on each TiDB instance
+- CPS by Instance: command per second of each TiProxy instance
+- CPS by Backend: command per second of each TiDB instance
+- CPS by CMD: command per second grouped by SQL command type
 
 ## Balance
 
-- Backend Connections: connection counts between each TiDB instance and each TiProxy instance. 
-- Session Migrations: session migrations happened on all TiProxy instances, recording sessions on which TiDB instance migrated to the other.
+- Backend Connections: connection counts between each TiDB instance and each TiProxy instance. For example, `10.24.31.1:6000 | 10.24.31.2:4000` indicates the connections between TiProxy instance `10.24.31.1:6000` and TiDB instance `10.24.31.2:4000`
+- Session Migration OPM: the number of session migrations that happened every minute, recording sessions on which TiDB instance migrated to the other. For example, `succeed: 10.24.31.2:4000 => 10.24.31.3:4000` indicates the number of sessions that are successfully migrated from TiDB instance `10.24.31.2:4000` to TiDB instance `10.24.31.3:4000`
 - Session Migration Duration: average, p95, p99 session migration duration.
 
 ## Backend
 
-- Get Backend Count: how many times did TiProxy instances try to connect the backend.
-- Get Backend Duration: average, p95, p99 duration of connecting backend, useful for debugging why TiProxy can not establish healthy connections.
-- Ping Backend Duration: latencies between each TiDB instance and each TiProxy instance.
+- Get Backend Duration: the average, p95, p99 duration of TiProxy connecting to a TiDB instance
+- Ping Backend Duration: the network latency between each TiProxy instance and each TiProxy instance. For example, `10.24.31.1:6000 | 10.24.31.2:4000` indicates the network latency between TiProxy instance `10.24.31.1:6000` and TiDB instance `10.24.31.2:4000`
+- Health Check Cycle: the duration of a cycle of the health check between a TiProxy instance and all TiDB instances. For example, `10.24.31.1:6000` indicates the duration of the latest health check that TiProxy instance `10.24.31.1:6000` executes on all the TiDB instances. If this duration is higher than 3 seconds, TiProxy may not be timely to refresh the backend TiDB list