--- title: MSSQL NRDOT metrics reference source: https://docs.newrelic.com/docs/opentelemetry/database/mssql/metrics-reference --- > #### 💡 PREVIEW > > We're still working on this feature, but we'd love for you to try it out! > > This feature is currently provided as part of a preview pursuant to our [pre-release policies](https://docs.newrelic.com/docs/licenses/license-information/referenced-policies/new-relic-pre-release-policy/). Monitor your SQL Server database performance with comprehensive metrics collected by the NRDOT Collector. By default, New Relic collects the metrics referenced in the [Available metrics](#default) section. You can enhance your monitoring by enabling your desired metrics listed in the [Additional metrics](#additional-metrics) section. ## Available metrics [#default] The following metrics are collected automatically for New Relic UI functionality. These are enabled by default and work on any platform via a direct SQL Server connection. **Default metrics** | Metric | Description | Unit | Type | | ---------------------------------------- | ------------------------------------------------------------------------------------------------- | ------------------ | -------------- | | `sqlserver.batch.request.rate` | Number of batch requests received by SQL Server | `{requests}/s` | Gauge (double) | | `sqlserver.batch.sql_compilation.rate` | Number of SQL compilations needed | `{compilations}/s` | Gauge (double) | | `sqlserver.batch.sql_recompilation.rate` | Number of SQL recompilations needed | `{compilations}/s` | Gauge (double) | | `sqlserver.lock.wait.rate` | Number of lock requests resulting in a wait | `{requests}/s` | Gauge (double) | | `sqlserver.page.buffer_cache.hit_ratio` | Pages found in the buffer pool without having to read from disk | `%` | Gauge (double) | | `sqlserver.page.life_expectancy` | Time a page will stay in the buffer pool. Available attributes: `performance_counter.object_name` | `s` | Gauge (int) | | `sqlserver.user.connection.count` | Number of users connected to the SQL Server | `{connections}` | Gauge (int) | ## Additional metrics [#additional-metrics] The following metrics are disabled by default but can be enabled for deeper insights into SQL Server performance and health. These metrics are organized by functionality and most require a direct SQL Server connection. **Batch / Compilation metrics** | Metric | Description | Unit | Type | | ----------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------- | -------------- | | `sqlserver.attention.rate` | Number of SQL attentions (client cancellation interrupts) received per second | `{attentions}/s` | Gauge (double) | | `sqlserver.batch.compilation.utilization` | Number of SQL compilations per batch request | `1` | Gauge (double) | | `sqlserver.batch.page_split.utilization` | Number of page splits per batch request | `1` | Gauge (double) | | `sqlserver.recompilation.ratio` | Ratio of SQL recompilations to compilations, expressed as a percentage | `%` | Gauge (double) | | `sqlserver.parameterization.rate` | Rate of auto-parameterization activity, broken down by result. Available attributes: `sqlserver.parameterization.result` (`auto_attempted`, `safe`, `unsafe`, `failed`, `forced`) | `{params}/s` | Gauge (double) | | `sqlserver.plan.execution.rate` | Rate of plan executions, classified by plan guide result. Available attributes: `sqlserver.plan.guidance.result` (`guided`, `misguided`) | `{executions}/s` | Gauge (double) | **Database general metrics** | Metric | Description | Unit | Type | | ------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------- | -------------- | | `sqlserver.database.backup_or_restore.rate` | Total number of backups/restores | `{backups_or_restores}/s` | Gauge (double) | | `sqlserver.database.count` | The number of databases. Available attributes: `database.status` (`online`, `restoring`, `recovering`, `pending_recovery`, `suspect`, `offline`) | `{databases}` | Gauge (int) | | `sqlserver.database.execution.errors` | Number of execution errors | `{errors}` | Gauge (int) | | `sqlserver.database.file.size` | Size of database files. Available attributes: `file_type`, `db.namespace` | `By` | Gauge (int) | | `sqlserver.database.full_scan.rate` | The number of unrestricted full table or index scans | `{scans}/s` | Gauge (double) | | `sqlserver.database.transactions.active` | Number of active transactions in the database. Available attributes: `db.namespace` | `{transactions}` | Gauge (int) | | `sqlserver.deadlock.rate` | Total number of deadlocks | `{deadlocks}/s` | Gauge (double) | **Database — I/O & Latency metrics** | Metric | Description | Unit | Type | | ----------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ------------------------ | | `sqlserver.database.io` | The number of bytes of I/O on this file. Available attributes: `physical_filename`, `logical_filename`, `file_type`, `direction` | `By` | Sum (cumulative, int) | | `sqlserver.database.latency` | Total time that the users waited for I/O issued on this file. Available attributes: `physical_filename`, `logical_filename`, `file_type`, `direction` | `s` | Sum (cumulative, double) | | `sqlserver.database.operations` | The number of operations issued on the file. Available attributes: `physical_filename`, `logical_filename`, `file_type`, `direction` | `{operations}` | Sum (cumulative, int) | | `sqlserver.database.page_file.size` | Reserved space allocated to the database, broken down by usage state. Available attributes: `db.namespace`, `page_file.state` (`used`, `free`, `total`) | `By` | Gauge (int) | **Failover Cluster / Always-On Availability Groups metrics** | Metric | Description | Unit | Type | | ----------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------- | -------------- | | `sqlserver.failover_cluster.ag.cluster_type` | Cluster type of the Always-On Availability Group. Available attributes: `ag.name`, `ag.cluster_type` (`wsfc`, `external`, `none`, `unknown`) | `1` | Gauge (int) | | `sqlserver.failover_cluster.ag.failure_condition_level` | Failure condition level configured for the Availability Group (1-5). Available attributes: `ag.name` | `1` | Gauge (int) | | `sqlserver.failover_cluster.ag.health_check_timeout` | Health-check timeout configured for the Availability Group. Available attributes: `ag.name` | `ms` | Gauge (int) | | `sqlserver.failover_cluster.ag.required_sync_secondaries` | Number of synchronized secondary replicas required to commit on the Availability Group. Available attributes: `ag.name` | `{secondaries}` | Gauge (int) | | `sqlserver.failover_cluster.replica.database.queue_size` | Size of the log-send or redo queue for an AG database replica. Available attributes: `ag.name`, `replica.server_name`, `db.namespace`, `replica.queue_kind` (`log_send`, `redo`) | `By` | Gauge (int) | | `sqlserver.failover_cluster.replica.database.redo.rate` | Redo rate for an AG database replica. Available attributes: `ag.name`, `replica.server_name`, `db.namespace` | `By/s` | Gauge (double) | | `sqlserver.failover_cluster.replica.flow_control_time` | Cumulative time spent in AG flow control, in milliseconds per second observed | `ms` | Gauge (double) | | `sqlserver.failover_cluster.replica.role` | Role of the availability replica. Available attributes: `ag.name`, `replica.server_name`, `replica.role` (`primary`, `secondary`, `resolving`, `unknown`) | `1` | Gauge (int) | | `sqlserver.failover_cluster.replica.synchronization_health` | Synchronization health of the availability replica. Available attributes: `ag.name`, `replica.server_name`, `replica.sync_health` (`healthy`, `partially_healthy`, `not_healthy`, `unknown`) | `1` | Gauge (int) | **Index & Search metrics** | Metric | Description | Unit | Type | | ----------------------------- | ------------------------------ | -------------- | -------------- | | `sqlserver.index.search.rate` | Total number of index searches | `{searches}/s` | Gauge (double) | **Latch metrics** | Metric | Description | Unit | Type | | -------------------------------------------- | ------------------------------------------------------------------------------------------------------------------ | ---------------- | ------------------------ | | `sqlserver.latch.superlatch.count` | Number of superlatches currently active | `{superlatch}` | Gauge (int) | | `sqlserver.latch.superlatch.transition.rate` | Rate of superlatch promotions or demotions. Available attributes: `transition.direction` (`promotion`, `demotion`) | `{transition}/s` | Gauge (double) | | `sqlserver.latch.wait.rate` | Number of latch waits per second | `{wait}/s` | Gauge (double) | | `sqlserver.latch.wait_time.avg` | Average time spent waiting for latches (lighter-weight synchronization) | `s` | Gauge (double) | | `sqlserver.latch.wait_time.total` | Total latch wait time | `s` | Sum (cumulative, double) | **Locks (Detailed) metrics** | Metric | Description | Unit | Type | | ----------------------------- | ----------------------------------------------------------------------------------------------------------------- | -------------- | --------------------- | | `sqlserver.lock.timeout.rate` | Total number of lock timeouts | `{timeouts}/s` | Gauge (double) | | `sqlserver.lock.wait.count` | Cumulative count of lock waits that occurred. Available attributes: `workload_group.name` (`default`, `internal`) | `{wait}` | Sum (cumulative, int) | **Login / Logout metrics** | Metric | Description | Unit | Type | | ----------------------- | ----------------------- | ------------- | -------------- | | `sqlserver.login.rate` | Total number of logins | `{logins}/s` | Gauge (double) | | `sqlserver.logout.rate` | Total number of logouts | `{logouts}/s` | Gauge (double) | **Memory metrics** | Metric | Description | Unit | Type | | --------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ---------- | ------------------------ | | `sqlserver.memory.area` | Amount of memory used by the SQL Server memory pool. Available attributes: `memory.pool` (`target`, `total`, `sql_cache`, `optimizer`, `connection`, `granted_workspace`, `max_workspace`) | `By` | Gauge (int) | | `sqlserver.memory.cache.object.count` | Number of cache objects in the SQL Server cache. Available attributes: `cache.state` (`in_use`, `total`) | `{object}` | Gauge (int) | | `sqlserver.memory.grants.pending.count` | Total number of memory grants pending | `{grants}` | Sum (cumulative, int) | | `sqlserver.memory.page.count` | Number of pages in the SQL Server buffer pool. Available attributes: `page.pool` (`cache`, `total`, `target`, `database`, `stolen`, `reserved`, `free`) | `{page}` | Gauge (int) | | `sqlserver.memory.usage` | Total memory in use. Available attributes: `workload_group.name` (`default`, `internal`) | `KB` | Sum (cumulative, double) | **OS-Level metrics** | Metric | Description | Unit | Type | | --------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ | ----------- | ------------------------ | | `sqlserver.computer.uptime` | Computer uptime | `{seconds}` | Gauge (int) | | `sqlserver.cpu.count` | Number of CPUs | `{CPUs}` | Gauge (int) | | `sqlserver.os.disk.size` | Total disk space across volumes hosting SQL Server database files | `By` | Gauge (int) | | `sqlserver.os.memory.usage` | Amount of system physical memory observed by SQL Server. Available attributes: `memory.state` (`available`, `total`) | `By` | Gauge (int) | | `sqlserver.os.memory.utilization` | Fraction of system physical memory in use by the SQL Server process | `1` | Gauge (double) | | `sqlserver.os.scheduler.runnable_tasks.count` | Total number of runnable tasks across online schedulers | `{tasks}` | Gauge (int) | | `sqlserver.os.wait.duration` | Total wait time for this wait type. Available attributes: `wait.category`, `wait.type` | `s` | Sum (cumulative, double) | | `sqlserver.os.wait.tasks.count` | Cumulative number of tasks that have waited on this wait type since SQL Server startup. Available attributes: `wait.category`, `wait.type` | `{tasks}` | Sum (cumulative, int) | **Page Buffer (Detailed) metrics** | Metric | Description | Unit | Type | | --------------------------------------------------- | ---------------------------- | ------------- | -------------- | | `sqlserver.page.buffer_cache.free_list.stalls.rate` | Number of free list stalls | `{stalls}/s` | Gauge (int) | | `sqlserver.page.lookup.rate` | Total number of page lookups | `{lookups}/s` | Gauge (double) | **Processes / Sessions metrics** | Metric | Description | Unit | Type | | ----------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------- | ----------- | | `sqlserver.process.count` | Number of SQL Server processes (user sessions), broken down by status. Available attributes: `process.status` (`background`, `dormant`, `preconnect`, `runnable`, `running`, `sleeping`, `suspended`) | `{processes}` | Gauge (int) | | `sqlserver.processes.blocked` | The number of processes that are currently blocked | `{processes}` | Gauge (int) | **Replica metrics** | Metric | Description | Unit | Type | | ----------------------------- | -------------------------------------------------------------------------------------------------- | ------ | -------------- | | `sqlserver.replica.data.rate` | Throughput rate of replica data. Available attributes: `replica.direction` (`transmit`, `receive`) | `By/s` | Gauge (double) | **Resource Pool / Throttling metrics** | Metric | Description | Unit | Type | | --------------------------------------------------- | ---------------------------------------------------------------------------------- | ---------------- | -------------- | | `sqlserver.resource_pool.disk.operations` | The rate of operations issued. Available attributes: `direction` (`read`, `write`) | `{operations}/s` | Gauge (double) | | `sqlserver.resource_pool.disk.throttled.read.rate` | The number of read operations that were throttled in the last second | `{reads}/s` | Gauge (int) | | `sqlserver.resource_pool.disk.throttled.write.rate` | The number of write operations that were throttled in the last second | `{writes}/s` | Gauge (double) | **Tables metrics** | Metric | Description | Unit | Type | | ----------------------- | --------------------------------------------------------------------------------------------------------------------------- | ---------- | --------------------- | | `sqlserver.table.count` | The number of tables. Available attributes: `table.state` (`active`, `inactive`), `table.status` (`temporary`, `permanent`) | `{tables}` | Sum (cumulative, int) | **TempDB metrics** | Metric | Description | Unit | Type | | ---------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------- | ------------------------ | | `sqlserver.database.tempdb.space` | Total free space in temporary DB. Available attributes: `tempdb.state` (`free`, `used`) | `KB` | Sum (cumulative, int) | | `sqlserver.database.tempdb.version_store.size` | TempDB version store size | `KB` | Gauge (double) | | `sqlserver.tempdb.allocation.wait_time.total` | Cumulative wait time on tempdb allocation pages, broken down by page type. Available attributes: `allocation.page_type` (`gam`, `sgam`, `pfs`, `other`) | `s` | Sum (cumulative, double) | | `sqlserver.tempdb.contention.waiters.count` | Number of tempdb pagelatch wait types with at least one active waiter | `{waiters}` | Gauge (int) | | `sqlserver.tempdb.data_files.count` | Number of tempdb data files configured on the instance | `{files}` | Gauge (int) | | `sqlserver.tempdb.file.size` | Size of each tempdb data or log file. Available attributes: `file_type`, `tempdb.file.id` | `By` | Gauge (int) | | `sqlserver.tempdb.space.usage` | Space used by tempdb, broken down by allocation category. Available attributes: `tempdb.space_kind` (`user_objects`, `internal_objects`, `version_store`, `free`) | `By` | Gauge (int) | **Thread Pool metrics** | Metric | Description | Unit | Type | | ------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------- | ----------- | -------------- | | `sqlserver.thread_pool.tasks.count` | Number of SQL Server tasks broken down by state. Available attributes: `task.state` (`current`, `queued`, `waiting_for_threadpool`) | `{tasks}` | Gauge (int) | | `sqlserver.thread_pool.workers.count` | Number of SQL Server worker threads broken down by state. Available attributes: `worker.state` (`running`, `suspended_or_sleeping`) | `{workers}` | Gauge (int) | | `sqlserver.thread_pool.workers.max` | Maximum number of SQL Server worker threads configured on the instance | `{workers}` | Gauge (int) | | `sqlserver.thread_pool.workers.utilization` | Fraction of configured SQL Server worker threads currently running | `1` | Gauge (double) | **Transactions (Detailed) metrics** | Metric | Description | Unit | Type | | ----------------------------------------------- | ---------------------------------------------------------------------- | ------------------ | ------------------------ | | `sqlserver.transaction.delay` | Time consumed in transaction delays | `ms` | Sum (cumulative, double) | | `sqlserver.transaction.longest_running_time` | Age in seconds of the longest currently-open transaction on the server | `s` | Gauge (double) | | `sqlserver.transaction.mirror_write.rate` | Total number of mirror write transactions | `{transactions}/s` | Gauge (double) | | `sqlserver.transaction.version_cleanup.rate` | Cumulative bytes cleaned from the tempdb version store | `By` | Sum (cumulative, double) | | `sqlserver.transaction.version_generation.rate` | Cumulative bytes of row versions written to the tempdb version store | `By` | Sum (cumulative, double) | ### Additional Windows metrics [#additional-windows-metrics] The following metrics are available on Windows platforms when using the NRDOT Collector with SQL Server. These metrics provide Windows-specific performance insights for SQL Server monitoring. **Additional Windows metrics** 13 metrics available on Windows platforms | Metric | Description | Unit | Type | | ---------------------------------------------------- | ----------------------------------------------------------------------------------------- | -------------------- | -------------- | | `sqlserver.computer.uptime` | System uptime counter | `s` | Gauge (double) | | `sqlserver.cpu.count` | Number of CPU cores available | `{cpu}` | Gauge (double) | | `sqlserver.memory.usage` | Memory usage by SQL Server process. Available attributes: `memory_type` | `By` | Gauge (double) | | `sqlserver.performance_counter.buffer.hit_ratio` | Percentage of pages found in the buffer cache | `%` | Gauge (double) | | `sqlserver.performance_counter.cache.hit_ratio` | Ratio of cache hits to cache lookups. Available attributes: `cache_type` | `%` | Gauge (double) | | `sqlserver.performance_counter.compilations.rate` | Number of SQL compilations per second | `{compilations}/s` | Gauge (double) | | `sqlserver.performance_counter.connections` | Number of user connections to SQL Server | `{connections}` | Gauge (double) | | `sqlserver.performance_counter.locks.count` | Number of current locks. Available attributes: `lock_type` | `{locks}` | Gauge (double) | | `sqlserver.performance_counter.locks.timeout.rate` | Number of lock timeouts per second | `{timeouts}/s` | Gauge (double) | | `sqlserver.performance_counter.memory.grant_pending` | Total number of processes waiting for memory grants | `{processes}` | Gauge (double) | | `sqlserver.performance_counter.page.operations.rate` | Number of physical database page operations per second. Available attributes: `page_type` | `{operations}/s` | Gauge (double) | | `sqlserver.performance_counter.recompilations.rate` | Number of SQL recompilations per second | `{recompilations}/s` | Gauge (double) | | `sqlserver.performance_counter.transactions.rate` | Number of transactions per second. Available attributes: `database` | `{transactions}/s` | Gauge (double) | ## Amazon RDS limitations [#rds-limitations] When monitoring an Amazon RDS for SQL Server instance, certain metrics may report `0` or not be collected due to RDS service restrictions and SQL Server edition limitations. > #### ⚠️ IMPORTANT > > The following limitations apply specifically to SQL Server instances running on Amazon RDS. Self-hosted SQL Server deployments are not affected by these restrictions. **RDS metric limitations reference** | Metric | Limitation | Affected editions | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- | ----------------- | | `sqlserver.database.execution.errors` | Always reports `0`. SQL Server ML Services (Extensibility Framework) is not provisioned on any Amazon RDS SQL Server edition. | All editions | | `sqlserver.failover_cluster.ag.cluster_type`, `sqlserver.failover_cluster.ag.failure_condition_level`, `sqlserver.failover_cluster.ag.health_check_timeout`, `sqlserver.failover_cluster.ag.required_sync_secondaries`, `sqlserver.failover_cluster.replica.database.queue_size`, `sqlserver.failover_cluster.replica.database.redo.rate`, `sqlserver.failover_cluster.replica.role`, `sqlserver.failover_cluster.replica.synchronization_health` | Not collected. Always On Availability Groups require Multi-AZ deployment, unavailable on Web and Express editions. | Web, Express | | `sqlserver.failover_cluster.replica.flow_control_time`, `sqlserver.replica.data.rate`, `sqlserver.transaction.delay`, `sqlserver.transaction.mirror_write.rate` | Emitted but always reports `0`. These measure AG replica activity unavailable without Multi-AZ. | Web, Express | For more information, refer to [Amazon RDS for SQL Server: Unsupported features](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/SQLServer.Concepts.General.FeatureNonSupport.html) and [Multi-AZ for Amazon RDS for SQL Server](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_SQLServerMultiAZ.html). ## Related documentation [#related-docs] [Linux instrumentation for self-hosted environments](https://docs.newrelic.com/docs/opentelemetry/database/mssql/linux-hosted) Learn how to set up MSSQL monitoring in self-hosted Linux environments with New Relic. [Windows instrumentation for self-hosted environments](https://docs.newrelic.com/docs/opentelemetry/database/mssql/windows-hosted) Learn how to set up MSSQL monitoring in self-hosted Windows environments with New Relic. [Set up APM-database correlation](https://docs.newrelic.com/docs/opentelemetry/database/capabilities/db-apm) Learn how to correlate your application performance with database operations in New Relic.