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sys.dm_db_resource_stats (Azure SQL Database and Azure SQL Managed Instance)

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Applies to: Azure SQL Database Azure SQL Managed Instance

Returns CPU, I/O, and memory consumption for a database in Azure SQL Database or an Azure SQL Managed Instance. One row exists for every 15 seconds, even if there is no activity. Historical data is maintained for approximately one hour.

Columns Data Type Description
end_time datetime UTC time indicates the end of the current reporting interval.
avg_cpu_percent decimal (5,2) Average compute utilization in percentage of the limit of the service tier.
avg_data_io_percent decimal (5,2) Average data I/O utilization in percentage of the limit of the service tier. For Hyperscale databases, see Data IO in resource utilization statistics.
avg_log_write_percent decimal (5,2) Average transaction log writes (in MBps) as percentage of the service tier limit.
avg_memory_usage_percent decimal (5,2) Average memory utilization in percentage of the limit of the service tier.

This includes memory used for buffer pool pages and storage of In-Memory OLTP objects.
xtp_storage_percent decimal (5,2) Storage utilization for In-Memory OLTP as a percentage of pool limit at the end of the reporting interval. This includes memory used for storage of the following In-Memory OLTP objects: memory-optimized tables, indexes, and table variables. It also includes memory used for processing ALTER TABLE operations on memory-optimized tables.

Returns 0 if In-Memory OLTP is not used in the database.
max_worker_percent decimal (5,2) Maximum concurrent workers (requests) in percentage of the limit of the database's service tier.
max_session_percent decimal (5,2) Maximum concurrent sessions in percentage of the limit of the database's service tier.
dtu_limit int Current max database DTU setting for this database during this interval. For databases using the vCore-based model, this column is NULL.
cpu_limit decimal (5,2) Number of vCores for this database during this interval. For databases using the DTU-based model, this column is NULL.
avg_instance_cpu_percent decimal (5,2) Average CPU utilization by the database engine instance hosting the pool, as a percentage of instance limit. Reported at one minute granularity and includes CPU utilization by both user and internal workloads.
avg_instance_memory_percent decimal (5,2) Average memory usage for the SQL Server instance hosting the database. Includes memory utilization by both user and internal workloads.
avg_login_rate_percent decimal (5,2) Identified for informational purposes only. Not supported. Future compatibility is not guaranteed.
replica_role int Represents the current replica's role with 0 as primary, 1 as secondary, and 2 as forwarder (geo-secondary's primary). You will see "1" when connected with ReadOnly intent to all readable secondaries. If connecting to a geo-secondary without specifying ReadOnly intent, you should see "2" (connecting to the forwarder).

Tip

For more context about these limits and service tiers, see the topics Service Tiers, Manually tune query performance in Azure SQL Database, and SQL Database resource limits and resource governance.

Permissions

This view requires VIEW DATABASE STATE permission.

Remarks

The data returned by sys.dm_db_resource_stats is expressed as a percentage of the maximum allowed limits for the service tier/performance level that you are running.

If the database was failed over to another server within the last 60 minutes, the view will only return data for the time since that failover.

For a less granular view of this data with longer retention period, use the sys.resource_stats catalog view in Azure SQL Database, or the sys.server_resource_stats catalog view in Azure SQL Managed Instance. This view captures data every 5 minutes and maintains historical data for 14 days. For more information, see sys.resource_stats or sys.server_resource_stats.

When a database is a member of an elastic pool, resource statistics presented as percent values are expressed as the percent of the max limit for the databases as set in the elastic pool configuration.

Example

The following example returns resource utilization data ordered by the most recent time for the currently connected database in Azure SQL Database or Azure SQL Managed Instance.

SELECT * FROM sys.dm_db_resource_stats ORDER BY end_time DESC;

The following example identifies the average DTU consumption in terms of a percentage of the maximum allowed DTU limit in the performance level for the user database over the past hour. Consider increasing the performance level as these percentages near 100% on a consistent basis.

SELECT end_time,   
  (SELECT Max(v)    
   FROM (VALUES (avg_cpu_percent), (avg_data_io_percent), (avg_log_write_percent)) AS    
   value(v)) AS [avg_DTU_percent]   
FROM sys.dm_db_resource_stats;

The following example returns the average and maximum values for CPU percent, data and log I/O, and memory consumption over the last hour.

SELECT    
    AVG(avg_cpu_percent) AS 'Average CPU Utilization In Percent',   
    MAX(avg_cpu_percent) AS 'Maximum CPU Utilization In Percent',   
    AVG(avg_data_io_percent) AS 'Average Data IO In Percent',   
    MAX(avg_data_io_percent) AS 'Maximum Data IO In Percent',   
    AVG(avg_log_write_percent) AS 'Average Log Write I/O Throughput Utilization In Percent',   
    MAX(avg_log_write_percent) AS 'Maximum Log Write I/O Throughput Utilization In Percent',   
    AVG(avg_memory_usage_percent) AS 'Average Memory Usage In Percent',   
    MAX(avg_memory_usage_percent) AS 'Maximum Memory Usage In Percent'   
FROM sys.dm_db_resource_stats;

See Also