Foglight for Oracle (Cartridge) 5.9.3.10

By clicking the Generate Plan button the execution plan is generated and can be viewed. By clicking on the Compare Plan button a pop up will appear that allows comparing all available execution plans of the selected SQL statement.

Comparing Performance

Use the SQL PI Compare where differences in period activity illustrate underlying performance and monitoring issues. It helps you determine whether a comparison occurrence is an isolated incident or a sign of a potentially significant performance problem.

Compare can be access from the Performance tree.

The comparison can be of whole instances or selected dimension breakdowns (such as user or SQL). Use Compare to address questions such as:

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What caused a specific activity?

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What were the resource and load demands of today's instance activity compared with that of a previous day?

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Is an instance imposing different load levels now than previously?

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How do we explain the difference in a SQL performance compared with a previous period?

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What are the differences in program characteristics over two periods that caused different performance?

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After identifying the different resource usage, you can use compare to identify what caused this difference: Usage pattern? Different SQL behavior? Environmental problem?

The upper panes graphically displays the Workload or any other selected resource.

The middle Activity section displays the dimensions which were significant elements of the difference. Expanding the individual lines displays the dimension members which caused the difference and the composing metrics whose differences exceed the specified threshold.

Use the set of performance related metrics (defined by the chosen resource) to help you explain the difference in resource consumption; for example, a rise in I/O Wait might be explained by a rise in the quantity of physical reads.

Use the Comparison Parameters section in order to enter all the desired information for the cooperation. For example, time range, instance, dimension, time frames, resource.

Oracle Activity Drilldown

Use the Oracle Activity drilldown to carry out the operations described in the following topics:

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Viewing real-time informations about your system — for details, see Viewing the Foglight for Oracle Real-time Summary Page

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Reviewing usability and availability — using the Usability panel, either for a single instance or a RAC. For details, see Reviewing Instance Usability and Reviewing Cluster Usability.

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Viewing current and historical locks-related data — using the Locks panel, whose display changes when selecting a single instance or a RAC. For details, see Reviewing Locks Activity at the Cluster Level and Reviewing Locks Activity at the Instance Level.

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Viewing information about sessions that experienced the highest contention of a specified contention criterion — using the Sessions panel. For details, see Viewing Detailed Sessions Data.

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Viewing I/O activity of all datafiles on the cluster or instance — using the panel Overall Datafiles I/O, whose display changes when selecting a single instance or a RAC. For details, see Viewing Datafiles I/O Activity at the Cluster Level and Viewing Datafiles I/O Activity at the Instance Level.

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Viewing the user-defined collections, which were created from the Databases Administration dashboard using the User-defined Collections screen. For details, see Viewing User-Defined Collections.

Viewing the Foglight for Oracle Real-time Summary Page

The following image displays the main elements of the Foglight for Oracle real-time summary page. The table that follows the image identifies each element, and provides a link to display more information, corresponding to the logical dataflow within Foglight for Oracle Instance Homepage.

The main groups (panes) of gathered icons and gauges, which represent the main activity areas in the Oracle connection process, are as follows:

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Instance identification — used for identifying the instance, its type, and its properties. See Identifying the Instance .

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Components representing instance data flow — the main activity area in the Foglight for Oracle Instance Homepage includes several panes and flows that represent the data flow in the Oracle operation. The dataflow is represented in a top-down design, that is, from the session to the physical disk storage.

Identifying the Instance

Use the Instance identification indicators to identify the instance, its type and its operation period.

These indicators are:

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Instance name — identifies the instance.

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Specified time range — indicates the period of time for which data is being displayed (by default: last 60 minutes).

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Instance pane — contains the following indicators:

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DB Type — identifies whether the monitored database’s type is SQL Server, Sybase, DB2 or Oracle.

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DB Version — identifies the Oracle version number, along with the most recently installed service packs.

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Up Since — identifies the date and time when the instance was last started.


	NOTE: The pane’s initial view only shows the date; to display the time as well, hover the mouse or click the date text.

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OS Type — identifies the operating system’s version number, along with the most recently installed builds and service packs.


	NOTE: The pane’s initial view only shows the OS name; to display the build and service packs as well, hover the mouse or click the OS name’s text.

Monitoring the Instance

The indicators included in the Instance pane provide various details about the instance. All of the indicators display real-time behavior, color-coded for severity.


	NOTE: Clicking the Response Time, CPU (%) and Memory (%) indicators displays a popup that shows the metric’s value, plotted over time.

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Response Time — the time (in milliseconds) that elapses from the moment a query, which is supposed to represent the general workload, is submitted, until the application indicates that the query was executed.

As the response time is usually the starting point for investigation, the Response parameter leads to the SQL Instance Summary panel in the SQL Activity drilldown,

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CPU (%) and Memory (%) — the average CPU load and memory consumption (percentage), during the specified time range, of all CPU units that host the Oracle instance. This indicator displays the share of Oracle-incurred CPU load and memory consumption within the total figure.

Clicking the number on both icons displays a popup that shows the total CPU usage or memory consumption on the host, plotted over time.

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Number of CPUs — the number of CPU units on the instance’s host.

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Total RAM — the total amount (in megabytes) of the host’s physical memory.

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Free RAM — the total amount (in megabytes) of physical memory available to the applications

Monitoring General Sessions’ Statistics

The Sessions pane monitors all session types, that is: system, user, and Oracle sessions. Use this pane to view the response time compared with the number of sessions and the instance’s level of activity. A high response time value may result from a long queue, that is: an overly high percentage of active users.

Long queues can indicate one of the following issues:

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A massive workload — the system handles more users than it was initially designed to do.

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A bottleneck — lack of system resources prevents users from carrying out their transactions, resulting in wait events and an increasing number of sessions that remain active for prolonged periods.

The Sessions pane displays the total number of sessions, distributed according to the following distinctions:

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Active vs. inactive sessions

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System (background) vs. User (foreground) sessions

The parameters in this pane lead to the Activity > Sessions panel. For details, see Viewing Detailed Sessions Data .

The Client applications represented graphically in the Sessions pane communicate with Oracle by sending and receiving network packets and by submitting SQL statements for execution by Oracle. The flows, described in the following table, help indicate performance issues if their values are too low.

Table 6. Monitoring General Sessions’ Statistics
Flow	Description
Executions	The rate per second of calls (both user and recursive) that executed SQL statements.
Received packets	The rate at which network packets are being received by Oracle from Client applications. When this icon’s color is yellow, clicking it displays text that describes the deviations that triggered this display, along with a representation of the rate at which Oracle is encountering network packet errors.
Sent packets	The rate at which network packets are being sent from Oracle to Client applications. When this icon’s color is yellow, clicking it displays text that describes the deviations that triggered this display, along with a representation of the rate at which Oracle is encountering network packet errors.

Monitoring the Data Guard Service

Use the Data Guard section for monitoring Oracle Data Guard on primary databases. This section displays the gap between the last archive log on the primary database and last applied archive log on the standby database.

Oracle Data Guard can be configured as either physical or logical standby. For details about the preparations required for monitoring each of these setups, see Monitoring the Data Guard physical standby and Working with logical standby (SQL Apply) .

As Oracle Data Guard supports physical standby databases that use Redo Apply technology, use this section to monitor the rate of applying redo log files on standby database instance.


	IMPORTANT: The Data Guard section displays data only if the Data Guard service is configured.


	NOTE: Starting from Oracle 11g, Oracle provides the Active Data Guard option, which allows the standby to be read-only mode and at the same time to receive changes received from the primary node.

Monitoring the Data Guard physical standby

To prepare the physical standby:

Ensure that the Standby Database is in receiving mode.

Use sqlplus to connect to the Primary Database as SYS user.

Create the standby Foglight schema owner.

Run the privileges granting script for granting privileges to the created standby user, still from primary database. This script can be downloaded from the Connection Details screen.

If the Data Guard mode being used is Active Data Guard, proceed to Step 6. Otherwise proceed to the next step.

Switch to read-only mode on the standby database.


	IMPORTANT: Switching to read-only is only for the standby user availability check; there is no need to stay in that mode after the checkup.

Ensure that the Foglight schema owner is available on the standby database.

Open a browser and run the Oracle Monitoring Installer wizard.

Select Add a New Instance.

Specify the standby database credentials and connection details (the user that was created in Step 4).

Click Verify Connectivity

After connectivity verification is completed successfully, start monitoring the physical standby database.

Working with logical standby (SQL Apply)

To prepare the logical standby:

Use sqlplus to connect to the Logical standby as SYS user.

Create the standby Foglight schema owner

Open a browser and run the Oracle Monitoring Installer wizard.

Continue the Oracle Monitoring Installer process as usual, using the Logical standby user credentials and connection details

After connectivity verification is completed successfully, start monitoring the logical standby database.

Monitoring the Workload

The Workload chart displays the workload of the average active sessions, plotted over time.

The workload can be plotted as either:

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Baseline — workload plotted over time.

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Breakdown — the amount of time the database spent waiting for various wait events, plotted over time.

To display the wait events breakdown, click the arrow to the right of the Breakdown link.

Monitoring Process Activity

The Process Activity pane enables the monitoring of the processes ran by the Oracle instance, using performance indicators such as the total number of blocked processes and the rate per second of parses that are carried out during the most recent sample.

The Process Activity pane displays the following parameters.

Table 7. Process Activity pane parameters
Parameter	Description
Recent Executions	The number of statements executed during the most recent sample.
Blocked Processes	The average number of blocked processes that were collected during the specified time range. Blocked processes are processes that are waiting for another process to release a resource that the process is currently locking. Such processes can sometimes result in bottlenecks. The Blocked Process indicator changes its color when one or more processes become blocked.
Parses	Total number of parse calls. This figure is the total of both hard parse calls (calls that require loading the SQL source code into RAM for parsing) and soft parse calls.
Concurrent Transactions	The number of currently running transactions.

For further details, see Reviewing Instance Usability .

To communicate with the Oracle memory, the Oracle processes use logical reads and soft and hard parses, represented as flows in the homepage.

Monitoring Memory Activity

The Memory Activity session provides a view on the Oracle instance’s memory utilization, as described in the following table.

Table 8. Monitoring Memory Activity
Section	Metric	Description
SGA	Total (MB)	The actual size currently allocated to the System Global Area (SGA) memory.
	Buffer Cache (MB)	The amount of memory currently allocated to the buffer cache. The buffer cache, which is used for caching frequently accessed data blocks, is normally the largest memory cache used by Oracle.
	Shared Pool (MB)	The size of the shared pool. The shared pool caches SQL statements, PL/SQL programs, object definitions, and session memory for MTS sessions. Performance can improve when the shared pool is sized properly, thereby avoiding re-parsing and reloading.
	Buffer Cache Hit (%)	The percentage of block requests, which found the block in the buffer cache, out of the entire block requests (including requests that required disk reads).
Library Cache Hit (%)		The effectiveness of the library cache, computed by comparing the number of queries submitted to Oracle server for execution, which found the parsed execution plan in the library cache (soft parsing), with the entire number of queries submitted during the specified time range (including queries that required the parsing of a new statement, also known as “hard parsing”).
PGA	Total (MB)	The actual size currently allocated to the Program Global Area (PGA) memory.
PGA	PGA Hit (%)	The percentage PGA cache hit ratio. When the value of this metric is 100%, it indicates that all work areas executed by the system processed the entire input data using exclusively the PGA memory, thereby making optimal use of this memory. Any lower value indicates that at least one work area required one or more extra passes over the input data.