Get SQL Server CPU Utilization Query

The Get SQL Server CPU Utilization Query provides valuable insights into the CPU usage of a SQL Server. With the increasing amount of data being processed and the complexity of queries, monitoring CPU utilization is crucial for efficient database management. The query allows administrators to identify potential bottlenecks, optimize query performance, and ensure the smooth functioning of the SQL Server.

This query has a significant impact on the overall performance of a SQL Server. By analyzing the CPU utilization, administrators can identify high-usage queries, troubleshoot performance issues, and make informed decisions to optimize resource allocation. With accurate CPU utilization data, administrators can proactively manage server capacity, improve response times, and enhance the overall user experience.

Introduction

SQL Server CPU utilization is an important aspect to monitor and manage for optimal performance in any SQL Server environment. The CPU is responsible for executing queries, handling data processing, and running other tasks necessary for the server to function. Monitoring the CPU utilization helps identify potential bottlenecks and allows for timely optimizations. In this article, we will explore various SQL Server CPU utilization queries that can provide valuable insights into the performance of your SQL Server.

1. Query for CPU utilization by database

When dealing with a multi-database SQL Server environment, it's helpful to have visibility into the CPU utilization of individual databases. This allows you to identify which databases are consuming the most CPU resources and potentially optimize their queries or configurations.

To get the CPU utilization by database, you can use the following query:

SELECT
    DB_NAME(st.dbid) AS DatabaseName,
    COUNT(*) AS NumberOfExecutions,
    SUM(qs.total_worker_time) AS TotalCPUUsage
FROM
    sys.dm_exec_query_stats AS qs
    CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS st
GROUP BY
    DB_NAME(st.dbid)
ORDER BY
    TotalCPUUsage DESC;

This query uses the sys.dm_exec_query_stats and sys.dm_exec_sql_text dynamic management views to retrieve information about the CPU usage and the associated database for each query execution plan in the SQL Server instance. The DB_NAME function is used to retrieve the database name based on the dbid column.

Example:

When you execute the above query, you will get a result set with the following columns:

DatabaseName	NumberOfExecutions	TotalCPUUsage
Database1	100	2000
Database2	50	1500
Database3	75	1000

2. Query for CPU utilization by session

Understanding the CPU utilization by individual sessions can help in identifying processes or queries that are consuming excessive resources. It allows you to pinpoint the culprits and take appropriate actions, such as optimizing queries or terminating long-running sessions if necessary.

To get the CPU utilization by session, you can use the following query:

SELECT
    session_id AS SessionID,
    login_time AS LoginTime,
    last_request_start_time AS LastRequestStartTime,
    total_worker_time AS TotalCPUUsage
FROM
    sys.dm_exec_sessions
WHERE
    status = 'running'
ORDER BY
    total_worker_time DESC;

This query retrieves the session ID, login time, last request start time, and total CPU usage for all running sessions in the SQL Server instance. The sys.dm_exec_sessions dynamic management view provides information about the active sessions in the SQL Server.

Example:

Executing the above query will provide a result set with the following columns:

SessionID	LoginTime	LastRequestStartTime	TotalCPUUsage
55	2021-01-01 09:00:00	2021-01-01 09:10:00	5000
78	2021-01-02 14:30:00	2021-01-02 15:00:00	3000
102	2021-01-03 11:45:00	2021-01-03 12:30:00	2000

3. Query for CPU utilization trend

Monitoring the CPU utilization trend over a specific time period helps in understanding the workload patterns and detecting anomalies. It allows you to identify peak usage hours, periods of increased resource demand, and potential performance issues.

To get the CPU utilization trend, you can use the following query:

SELECT
    DATEADD(MINUTE, (DATEDIFF(MINUTE, GETDATE(), GETUTCDATE())), [timestamp]) AS UTCTimestamp,
    SQLProcessUtilization AS CPUUtilization
FROM
    sys.dm_os_ring_buffers
WHERE
    ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR'
    AND record_id IN (
        SELECT
            MAX(record_id)
        FROM
            sys.dm_os_ring_buffers
        WHERE
            ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR'
            AND (record_id > (SELECT MAX(record_id) - 1440 FROM sys.dm_os_ring_buffers WHERE ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR'))
    )
ORDER BY
    UTCTimestamp;

This query retrieves the CPU utilization recorded in the scheduler monitor ring buffer for the past 24 hours. It calculates the UTC timestamp using the GETUTCDATE function to convert the local timestamp to UTC.

Example:

When you execute the above query, you will get a result set with the following columns:

UTCTimestamp	CPUUtilization
2021-01-01 00:00:00	80
2021-01-01 00:01:00	75
2021-01-01 00:02:00	85

4. Query for CPU utilization by resource governor classifier function

If resource governor is enabled in your SQL Server environment, you can track the CPU utilization by the resource governor classifier function. This helps in monitoring and managing CPU usage based on workload classification, allowing for better resource allocation and control.

To get the CPU utilization by the resource governor classifier function, you can use the following query:

SELECT
    name AS ClassifierFunction,
    cpu_time_ms AS CPUUsage
FROM
    sys.dm_resource_governor_resource_pools AS rgp
    JOIN sys.dm_exec_requests AS er ON rgp.pool_id = er.requested_resource_pool_id
CROSS APPLY
    sys.dm_exec_query_plan(er.plan_handle) AS qp
WHERE
    er.command = 'SELECT';

This query retrieves the resource governor classifier function name and the associated CPU usage for all requests in the SQL Server instance with the command type as 'SELECT'.

Example:

Executing the above query will provide a result set with the following columns:

ClassifierFunction	CPUUsage
Function1	1000
Function2	500
Function3	200

Exploring a Different Dimension of 'Get SQL Server CPU Utilization Query'

Now let's dive into another aspect of SQL Server CPU utilization queries, focusing on performance metrics and troubleshooting.

1. Query for CPU utilization by query execution plan

In SQL Server, the query execution plan plays a vital role in determining the CPU utilization. By analyzing the CPU usage at the query execution plan level, you can identify queries that are consuming excessive resources and optimize them for better performance.

To get the CPU utilization by query execution plan, you can use the following query:

SELECT
    qp.query_plan AS QueryPlan,
    qs.total_worker_time AS TotalCPUUsage
FROM
    sys.dm_exec_query_stats AS qs
    CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) AS qp
ORDER BY
    TotalCPUUsage DESC;

This query retrieves the query execution plan and the associated CPU usage for all query plans in the SQL Server instance. The sys.dm_exec_query_stats dynamic management view provides information about the query statistics, while the sys.dm_exec_query_plan dynamic management function retrieves the query execution plan.

Example:

Executing the above query will provide a result set with the following columns:

QueryPlan	TotalCPUUsage
Execution Plan XML	4000
Execution Plan XML	3500
Execution Plan XML	3000

2. Query for CPU utilization by cached queries

SQL Server has a query cache that stores the execution plans of frequently executed queries. By examining the CPU utilization by cached queries, you can identify high CPU usage queries and optimize them accordingly.

To get the CPU utilization by cached queries, you can use the following query:

SELECT
    qt.[text] AS Query,
    qs.total_worker_time AS TotalCPUUsage
FROM
    sys.dm_exec_query_stats AS qs
    CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) AS qt
ORDER BY
    TotalCPUUsage DESC;

This query retrieves the query text and the associated CPU usage for all cached queries in the SQL Server instance. The sys.dm_exec_sql_text dynamic management function is used to retrieve the query text based on the SQL handle.

Example:

Executing the above query will provide a result set with the following columns:

Query	TotalCPUUsage
SELECT * FROM Table1	2000
SELECT * FROM Table2	1500
SELECT * FROM Table3	1000

3. Query for CPU utilization by wait types

SQL Server keeps track of various wait types that indicate delays or resource contention within the system. By examining the CPU utilization by wait types, you can identify specific waits that contribute to high CPU usage and take appropriate actions to mitigate them.

To get the CPU utilization by wait types, you can use the following query:

SELECT
    wt.wait_type AS WaitType,
    SUM(qs.total_worker_time) AS TotalCPUUsage
FROM
    sys.dm_exec_query_stats AS qs
    JOIN sys.dm_os_wait_stats AS ws ON qs.plan_handle = ws.plan_handle
    JOIN sys.dm_os_waiting_tasks AS wt ON ws.waiting_task_address = wt.waiting_task_address
WHERE
    wt.wait_type LIKE '%CPU%'
GROUP BY
    wt.wait_type
ORDER BY
    TotalCPUUsage DESC;

This query retrieves the wait type and the associated CPU usage for all wait types related to CPU in the SQL Server instance. The sys.dm_os_wait_stats dynamic management view provides information about the wait statistics, while the sys.dm_os_waiting_tasks dynamic management view retrieves the details of the waiting tasks.

Example:

Executing the above query will provide a result set with the following columns:

How to Get SQL Server CPU Utilization Query

Monitoring the CPU utilization of your SQL Server is crucial for identifying performance issues and ensuring optimal performance. To obtain the CPU utilization query, follow these steps:

• Connect to the SQL Server using your preferred tool (SQL Server Management Studio, etc.).
• Open a new query window.
• Execute the following T-SQL statement:

SELECT
  SQLProcessUtilization AS 'SQL Server CPU Utilization',
  SystemIdle AS 'System Idle',
  100 - SystemIdle - SQLProcessUtilization AS 'Others'
FROM
  sys.dm_os_ring_buffers
WHERE
  ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR'
  AND record_id = (
    SELECT
      MAX(record_id)
    FROM
      sys.dm_os_ring_buffers
    WHERE
      ring_buffer_type = N'RING_BUFFER_SCHEDULER_MONITOR'
  );

The above query retrieves the CPU utilization information from the system view sys.dm_os_ring_buffers, specifically from the RING_BUFFER_SCHEDULER_MONITOR. It returns the SQL Server CPU utilization, system idle percentage, and other processes' CPU utilization percentage.

Frequently Asked Questions

Here are some common questions and answers related to retrieving the CPU utilization query in SQL Server.

1. How can I retrieve the CPU utilization query in SQL Server?

To retrieve the CPU utilization query in SQL Server, you can use the following query:

SELECT cpu_percent
FROM sys.dm_os_ring_buffers
WHERE ring_buffer_type = 'RING_BUFFER_SCHEDULER_MONITOR'
AND record_id = (
    SELECT MAX(record_id)
    FROM sys.dm_os_ring_buffers
    WHERE ring_buffer_type = 'RING_BUFFER_SCHEDULER_MONITOR'
)

This query utilizes the sys.dm_os_ring_buffers dynamic management view to retrieve the CPU utilization percentage. It filters for the 'RING_BUFFER_SCHEDULER_MONITOR' ring buffer type and selects the record with the highest record_id, which represents the most recent data.

2. Can I get historical CPU utilization data using this query?

No, the query provided retrieves the current CPU utilization data. If you need historical CPU utilization data, you will need to collect and store the data periodically using other methods like Extended Events or SQL Server Profiler.

3. What does the 'cpu_percent' column represent in the query result?

The 'cpu_percent' column in the query result represents the CPU utilization percentage at the time the query was executed. It indicates the portion of the CPU's capacity that is currently being used by SQL Server processes.

4. Is there a way to retrieve CPU utilization data for specific SQL Server instances?

Yes, you can modify the query to filter the CPU utilization data for specific SQL Server instances. Add an additional condition in the WHERE clause to match the desired SQL Server instance name:

SELECT cpu_percent
FROM sys.dm_os_ring_buffers
WHERE ring_buffer_type = 'RING_BUFFER_SCHEDULER_MONITOR'
AND record_id = (
    SELECT MAX(record_id)
    FROM sys.dm_os_ring_buffers
    WHERE ring_buffer_type = 'RING_BUFFER_SCHEDULER_MONITOR'
)
AND [sqlserver].[session_id] = @@SPID

By using the '[sqlserver].[session_id] = @@SPID' condition, the query will return the CPU utilization data for the current SQL Server instance only.

5. Can I monitor CPU utilization in real-time using this query?

No, the query provided retrieves the most recent CPU utilization data at the time of execution. To monitor CPU utilization in real-time, you can utilize tools like SQL Server Profiler, Extended Events, or third-party monitoring solutions that provide real-time performance monitoring capabilities.

Understanding how to monitor and analyze CPU utilization in SQL Server is crucial for maintaining the performance and stability of your database. By using the appropriate query, you can easily gather valuable information about CPU usage, such as the CPU utilization percentage and the top CPU-consuming queries.

Monitoring CPU utilization helps you identify potential bottlenecks and optimize query performance. By regularly checking CPU usage, you can proactively address any issues and ensure that your SQL Server environment is running efficiently. Remember to run the query during periods of peak activity to get an accurate measure of CPU usage.