# List of metrics In this section you can find a description of each metric type used by the driver and a list of all metrics provided by the driver. ## Metric types | Metric Type | Description | |---------------|------------------------------------------------------------------------------------------------------------------------------------| | Counter | Counters are atomic `long` values which can be incremented. | | Gauge | A Gauge is simply an action that returns the instantaneous measure of a value, where the value abitrarily increases and decreases. | | Meter | A Meter measures the rate at which an event occurs along with a total count of the occurances. | | Timer | A Timer allows us to measure the duration of a type of event, the rate of its occurrence and provide duration statistics. | ## Session level metrics | Name | Type | C# Property | Description | |-----------------------|---------|--------------------------------------------|-------------------------------------------------------------------------------------------------------------| | `connected-nodes` | Gauge | `SessionMetric.Gauges.ConnectedNodes` | The number of nodes to which the driver has at least one active connection. | | `cql-client-timeouts` | Counter | `SessionMetric.Counters.CqlClientTimeouts` | The number of timeouts in synchronous API calls like `ISession.Execute()` (related to `QueryAbortTimeout`). | | `bytes-received` | Meter | `SessionMetric.Meters.BytesReceived` | The number and rate of bytes received for the entire session. | | `bytes-sent` | Meter | `SessionMetric.Meters.BytesSent` | The number and rate of bytes sent for the entire session. | | `cql-requests` | Timer | `SessionMetric.Timers.CqlRequests` | The throughput and latency percentiles of CQL requests (overall duration of the `ISession.Execute()` call). | ## Node level metrics | Name | Type | C# Property | Description | |----------------------------------|---------|---------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | `pool.open-connections` | Gauge | `NodeMetric.Gauges.OpenConnections` | The number of connections open to this node for regular requests. | | `pool.in-flight` | Gauge | `NodeMetric.Gauges.InFlight` | The number of requests currently executing on the connections to this node. | | `cql-messages` | Timer | `NodeMetric.Timers.CqlMessages` | The throughput and latency percentiles of individual CQL messages sent to this node as part of an overall request. | | `bytes-sent` | Meter | `NodeMetric.Meters.BytesSent` | The number and rate of bytes sent to this node. | | `bytes-received` | Meter | `NodeMetric.Meters.BytesReceived` | The number and rate of bytes received from this node. | | `speculative-executions` | Counter | `NodeMetric.Counters.SpeculativeExecutions` | The number of speculative executions triggered by a slow response from this node. | | `errors.connection.init` | Counter | `NodeMetric.Counters.ConnectionInitErrors` | The number of errors encountered while trying to establish a connection to this node. Authentication errors are tracked separately in `errors.connection.auth`. | | `errors.connection.auth` | Counter | `NodeMetric.Counters.AuthenticationErrors` | The number of authentication errors encountered while trying to establish a connection to this node. | | `errors.request.read-timeouts` | Counter | `NodeMetric.Counters.ReadTimeouts` | The number of times this node replied with a `READ_TIMEOUT` error. | | `errors.request.write-timeouts` | Counter | `NodeMetric.Counters.WriteTimeouts` | The number of times this node replied with a `WRITE_TIMEOUT` error. | | `errors.request.unavailables` | Counter | `NodeMetric.Counters.UnavailableErrors` | The number of times this node replied with an `UNAVAILABLE` error. | | `errors.request.others` | Counter | `NodeMetric.Counters.OtherErrors` | The number of times this node replied with a server error that doesn’t fall under other `errors.request.*` metrics. | | `errors.request.aborted` | Counter | `NodeMetric.Counters.AbortedRequests` | The number of times a request was aborted before the driver even received a response from this node. Client timeouts are | | `errors.request.unsent` | Counter | `NodeMetric.Counters.UnsentRequests` | The number of times the driver failed to send a request to this node. | | `errors.request.client-timeouts` | Counter | `NodeMetric.Counters.ClientTimeouts` | The number of times the request failed due to a client-side timeout, when the client didn’t hear back from the server within `SocketOptions.ReadTimeoutMillis`. In this scenario, an `OperationTimedOutException` is thrown. | | `retries.read-timeout` | Counter | `NodeMetric.Counters.RetriesOnReadTimeout` | The number of **read timeout** errors on this node that caused the RetryPolicy to trigger a retry. | | `retries.write-timeout` | Counter | `NodeMetric.Counters.RetriesOnWriteTimeout` | The number of **write timeout** errors on this node that caused the RetryPolicy to trigger a retry. | | `retries.unavailable` | Counter | `NodeMetric.Counters.RetriesOnUnavailable` | The number of **unavailable** errors on this node that caused the RetryPolicy to trigger a retry. | | `retries.other` | Counter | `NodeMetric.Counters.RetriesOnOtherError` | The number of errors **other** than **read timeouts**, **write timeouts** and **unavailable** errors on this node that caused the RetryPolicy to trigger a retry. | | `retries.total` | Counter | `NodeMetric.Counters.Retries` | The total number of retries triggered by the RetryPolicy. | | `ignores.read-timeout` | Counter | `NodeMetric.Counters.IgnoresOnReadTimeout` | The number of **read timeout** errors on this node that were ignored by the RetryPolicy. | | `ignores.write-timeout` | Counter | `NodeMetric.Counters.IgnoresOnWriteTimeout` | The number of **write timeout** errors on this node that were ignored by the RetryPolicy. | | `ignores.unavailable` | Counter | `NodeMetric.Counters.IgnoresOnUnavailable` | The number of **unavailable** errors on this node that were ignored by the RetryPolicy. | | `ignores.other` | Counter | `NodeMetric.Counters.IgnoresOnOtherError` | The number of errors **other** than **read timeouts**, **write timeouts** and **unavailable** errors on this node that were ignored by the RetryPolicy. | | `ignores.total` | Counter | `NodeMetric.Counters.Ignores` | The total number of errors on this node that were ignored by the RetryPolicy. |