How To Check CPU Usage In Oracle Database

When it comes to optimizing the performance of an Oracle database, monitoring CPU usage is of paramount importance. The CPU is the brain of the system, responsible for executing all the tasks and processes. Understanding how to check CPU usage in Oracle Database can help identify any bottlenecks, prevent performance degradation, and ensure the database runs smoothly.

In order to check CPU usage in Oracle Database, there are several methods available. One option is to use the Oracle Enterprise Manager (OEM), a comprehensive management tool provided by Oracle. With OEM, administrators can easily monitor the CPU usage in real time, set thresholds to trigger alerts, and investigate any potential performance issues. Another approach is to utilize the V$OSSTAT view, which provides detailed information about the CPU usage, including both the idle and non-idle time. By regularly monitoring CPU usage and analyzing the data, database administrators can make informed decisions to optimize system performance and ensure efficient resource allocation.

Introduction: Understanding CPU Usage in Oracle Database

When it comes to optimizing the performance of an Oracle Database, understanding the CPU usage is crucial. The CPU, or Central Processing Unit, is responsible for executing instructions and performing calculations in the database. Monitoring and analyzing CPU usage can help identify bottlenecks, optimize resource allocation, and ensure efficient query execution.

In this article, we will explore various techniques to check CPU usage in Oracle Database and gain insights into its performance. We will cover both built-in Oracle tools and external monitoring solutions to provide a comprehensive understanding of CPU utilization.

1. Oracle Built-in Methods

1.1 V$SYSMETRIC and V$SYSSTAT Views

The V$SYSMETRIC and V$SYSSTAT views are valuable resources for monitoring CPU usage in Oracle Database. The V$SYSMETRIC view provides information about various system-level metrics, including CPU utilization. It displays metrics at different time intervals, allowing users to observe trends and identify potential issues.

On the other hand, the V$SYSSTAT view contains cumulative statistics for the system. It provides insights into CPU-related statistics and can assist in the analysis of CPU consumption over a specific period.

Statistic	Description
CPU_USAGE	Displays the total amount of CPU usage in centiseconds
IDLE_TIME	Indicates the time the CPU remains idle in hundredths of seconds
CPU_BUSY_TIME	Represents the time the CPU is not idle and performs work

By querying these views, DBAs and system administrators can access valuable information about CPU usage and take appropriate actions for optimization.

1.2 Enterprise Manager (EM)

Oracle Enterprise Manager (EM) provides a comprehensive graphical interface to monitor and manage a wide range of database parameters, including CPU usage. EM enables administrators to monitor CPU consumption at a system level, identify problem areas, and take corrective measures.

Through EM, users can view real-time and historical CPU usage metrics, such as CPU utilization percentage, top CPU-consuming sessions, and average active sessions. This information is invaluable for performance optimization and resource allocation.

1.3 Oracle Performance Hub

Oracle Performance Hub provides a consolidated view of database performance, including CPU utilization. It offers real-time and historical statistics, enabling users to identify hotspots, performance trends, and areas requiring optimization.

The Performance Hub includes valuable insights into CPU usage at various levels, such as database, host, and SQL statement. It highlights resource-intensive queries, identifies CPU-related bottlenecks, and facilitates efficient workload management.

2. External Monitoring Solutions

2.1 Oracle Enterprise Manager (OEM) Cloud Control

Oracle Enterprise Manager (OEM) Cloud Control is a powerful monitoring and management solution for Oracle Databases. It provides extensive insights into CPU usage through its comprehensive monitoring capabilities.

OEM Cloud Control allows DBAs to configure monitoring policies for CPU utilization and receive alerts in case of anomalies or overutilization. It also offers historical reports, trend analysis, and the ability to drill down into specific time intervals for in-depth analysis.

2.2 Third-Party Monitoring Tools

Several third-party monitoring tools are available in the market that specialize in database performance monitoring, including monitoring CPU usage in Oracle Database. These tools offer advanced features, such as real-time monitoring, predictive analytics, and customizable dashboards.

Examples of popular third-party tools include Quest Foglight, SolarWinds Database Performance Analyzer, and Dynatrace. These tools provide deep insights into CPU consumption, facilitate proactive performance tuning, and offer comprehensive monitoring solutions for complex database environments.

Exploring CPU Usage in Oracle Database: Advanced Techniques

In this section, we will delve into advanced techniques for checking CPU usage in Oracle Database.

1. AWR Reports

Oracle Automatic Workload Repository (AWR) provides comprehensive reports on database performance, including CPU utilization. These reports offer detailed statistics and actionable information to identify performance bottlenecks and tune the database environment.

By generating an AWR report, DBAs can gain insights into CPU usage over a specific period, such as hourly, daily, or weekly. The report includes statistical information, SQL statements consuming significant CPU resources, and wait events affecting CPU performance.

Section	Description
Host CPU Utilization	Displays CPU utilization percentages for different time intervals
SQL Statistics	Highlights SQL statements consuming the most CPU
Wait Events	Identifies wait events affecting the CPU, such as CPU scheduling delays

Using AWR reports, administrators can pinpoint resource-intensive queries, tune inefficient SQL statements, and optimize CPU usage for improved performance.

2. Oracle Performance Diagnostics and Tuning (PDT) Pack

The Oracle Performance Diagnostics and Tuning (PDT) Pack is a set of tools and features designed to enhance database performance and diagnose performance-related issues. It provides advanced diagnostics capabilities, including detailed CPU usage analysis.

With the PDT Pack, DBAs can capture and analyze real-time diagnostics, including CPU consumption. It offers visual representations of CPU usage over time, enabling administrators to identify patterns, spikes, and anomalies.

3. Oracle Real Application Testing (RAT)

Oracle Real Application Testing (RAT) is a powerful solution for testing and validating changes in the database environment. It can also be utilized for CPU-related analysis and workload testing.

RAT allows DBAs to capture real-time workloads and replay them in a controlled environment. By doing so, administrators can study the impact of changes on CPU consumption and identify any performance regressions.

4. Active Session History (ASH)

The Active Session History (ASH) feature in Oracle Database provides detailed information about active sessions, including CPU usage. It captures real-time data and stores it in memory, allowing administrators to analyze CPU utilization at the session level.

ASH data can be aggregated over time to identify CPU-intensive sessions, track their behavior, and correlate CPU usage with other performance metrics, such as I/O and wait events.

Conclusion

Checking CPU usage in Oracle Database is vital for ensuring optimal performance and resource utilization. With the built-in methods, such as the V$SYSMETRIC and V$SYSSTAT views, as well as tools like Enterprise Manager and Oracle Performance Hub, administrators can monitor and analyze CPU usage at both the system and database level.

To gain deeper insights, external monitoring solutions like OEM Cloud Control and third-party tools provide advanced features and comprehensive monitoring capabilities. Additionally, advanced techniques, including AWR reports, Oracle PDT Pack, RAT, and ASH, enable administrators to analyze CPU usage in detail and optimize performance.

By effectively monitoring and managing CPU usage, Oracle database administrators can ensure the smooth and efficient operation of their databases, resulting in improved performance and user satisfaction.

Checking CPU Usage in Oracle Database

In order to check the CPU usage in Oracle Database, you can follow the steps below:

• Connect to the Oracle Database using Oracle SQL Developer or any other SQL client.
• Run the following query: SELECT * FROM V$OSSTAT WHERE STAT_NAME = 'BUSY_TIME';
• This query will provide you with the total time the CPU has been busy in the database.
• Alternatively, you can use the following query to check the CPU usage at a specific point in time: SELECT VALUE/100 AS CPU_Usage FROM V$SYS_TIME_MODEL WHERE STAT_NAME = 'DB CPU';
• This query will give you the CPU usage as a percentage.

By executing these queries, you can easily monitor and analyze the CPU usage in your Oracle Database. This information can help you identify performance issues and optimize your database accordingly.

Frequently Asked Questions

Here are some commonly asked questions about how to check CPU usage in Oracle Database:

1. How can I check the current CPU usage in Oracle Database?

You can use the following query to check the current CPU usage in Oracle Database:

SELECT * FROM V$SYSSTAT WHERE NAME = 'CPU used by this session';

This query will provide you with the CPU usage for the current session in Oracle Database.

2. How can I check the CPU usage for a specific user in Oracle Database?

You can use the following query to check the CPU usage for a specific user in Oracle Database:

SELECT * FROM V$SESSION WHERE USERNAME = 'your_username';

This query will provide you with the CPU usage for the specified user in Oracle Database.

3. How can I check the CPU usage for a specific SQL statement in Oracle Database?

You can use the following query to check the CPU usage for a specific SQL statement in Oracle Database:

SELECT * FROM V$SQLSTATS WHERE SQL_TEXT LIKE '%your_sql_statement%';

This query will provide you with the CPU usage for the specified SQL statement in Oracle Database.

4. How can I check the overall CPU usage in Oracle Database?

You can use the following query to check the overall CPU usage in Oracle Database:

SELECT * FROM V$SYSSTAT WHERE NAME = 'CPU used by this session';

This query will provide you with the overall CPU usage in Oracle Database.

5. How can I check the historical CPU usage in Oracle Database?

You can use the following queries to check the historical CPU usage in Oracle Database:

SELECT * FROM DBA_HIST_SYSMETRIC_SUMMARY WHERE METRIC_NAME = 'CPU Usage Per Sec' AND BEGIN_TIME BETWEEN TO_DATE('your_start_date', 'DD-MM-YYYY HH24:MI:SS') AND TO_DATE('your_end_date', 'DD-MM-YYYY HH24:MI:SS');

SELECT * FROM DBA_HIST_SYSMETRIC_HISTORY WHERE METRIC_NAME = 'CPU Usage Per Sec' AND BEGIN_TIME BETWEEN TO_DATE('your_start_date', 'DD-MM-YYYY HH24:MI:SS') AND TO_DATE('your_end_date', 'DD-MM-YYYY HH24:MI:SS');

These queries will provide you with the historical CPU usage data in Oracle Database within the specified date range.

To summarize, checking CPU usage in an Oracle Database is a critical task for monitoring and optimizing performance. By understanding how to check CPU usage, database administrators can identify potential bottlenecks, allocate system resources effectively, and ensure smooth operation of the database.

There are several methods to check CPU usage in Oracle Database, such as using Oracle Enterprise Manager, querying dynamic performance views, or utilizing third-party monitoring tools. Whichever method you choose, it is important to regularly monitor CPU usage to maintain optimal performance and identify any issues that may arise.