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The other In Oracle wait states, such as Using CPU, do not apply to an object. See “In Oracle” on page 36.

Statement identifier vs. Oracle hash value

SQL statements in Precise for Oracle are assigned a numeric identifier (a 20-digit number that is divided into 4 sections, with dot separators) or a user-defined name. The numeric identifier is similar to, but not the same as, the hash value that Oracle assigns to a SQL statement. When Precise for Oracle calculates the numeric identifier, it ignores white space and case, unlike Oracle. It also takes into account whether Collapse Statements is switched on, in which case string literals are replaced with place holders or pseudo-bind variables.

Executions vs. opens and fetches

Precise for Oracle employs the following methods to determine how many times a statement has been executed.

• At each sample point, the Precise for Oracle Collector examines the equivalent area of the SGA that V$SQL maps on to and captures the number of executions of the statement that Oracle has recorded. (It also captures buffer gets and rows processed.

  Note:

  Info
  Precise for Oracle only increments the counters when the statement has finished executing similar to V$SQL.

• At each sample point, the Precise for Oracle Collector examines whether the session is opening or fetching from a cursor, that is executing a statement. Oracle does not provide enough information to allow the Collector to determine whether the session is opening (executing) the statement or fetching results, and therefore it counts both. This potential over-reading of the actual execution count may be offset by the fact that any sampling technology may miss some executions, particularly for fast-running statements.

Where possible, Precise for Oracle displays the number of executions that Oracle has recorded because it is more accurate. However, V$SQL only contains statistics about the statement; it does not tell you which session ran it. Therefore, it is not possible to accurately divide the number of executions between the sessions. This means that in the user interface, wherever you drill down in the context of a session (and this includes program and user), you will see opens and fetches. Where you drill down directly from the instance level to a statement, you will see executions. The Current tab, for example, displays opens and fetches because you always view a statement in the context of a session, whereas the Activity tab may display either executions or opens and fetches, depending on your navigation path. Other derived values, such as average response time, are only shown if the number of executions is available.

In Oracle time vs. Duration time

In Oracle time indicates the period that the entity consumed within the monitored box, not including IDLE time (sleep, waiting for user requests, etc.).

Duration time is the "wall clock time," , including idle and non-idle consumption periods. The following calculations are used:

Table 2-5 CalculationsCalculations    Description

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The following is an explanation based on an example statement using a parallel query.

When a session runs a statement for a table with parallel degree of n (4 degrees for example), the Oracle engine creates n new sessions to serve it (these sessions are called: "Parallel Server Agents"). Each of the parallel server agents runs as an individual entity and analyzes part of the requested data, while the original session (the one that you logged in with) is called the coordinator session. The last goal is to receive all the information from the parallel server agents and summarize (sort/filter/calculate/join) it. Usually the coordinator session will not perform an "In Oracle" operation. In fact it is waiting "All the time" when the parallel server agents are working. These parallel server agents can perform I/O / Locks / RAC operations - like any other regular session. These sessions (4 in our example) have the same session identifiers as the coordinator session. Therefore in the collector's aggregation phase all the sessions are aggregate into one row. For example, if a specific statement runs for 1 hour (wall clock time) you can see in the Activity tab that the statement consumed 4 hours "In Oracle" time. You can also find the parallel degree of the statement within the Activity tab.

Oracle statistics usage within Precise for Oracle

Precise for Oracle captures standard Oracle statistics that you can see in the V$SESSTAT table. However, the Collector reads the values in a low-overhead fashion directly from the SGA memory that the V$ tables map onto. Where necessary, the statistics are divided between the sessions executing each SQL statement and then aggregated to the user, program, and instance levels. You will see these statistics in the Current and Activity tabs, displayed as name-value pairs. Each statistic represents a different counter and has its own units. See Oracle’s documentation for more information on these statistics.

Precise Interpoint - how resource consumption of packaged applications is examined

Precise Interpoint is the only tool that helps the ERP administrator identify the exact cause of problems in ERP applications.

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Table 2-6 Mapping of Precise Interpoint entities per technologyTechnology    Entity

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Precise for Storage, Oracle version - how resource consumption of storage devices is examined

Precise for Storage, Oracle version supports EMC Symmetrix and Clariion, and Hitachi HDS. It offers a unique method to identify I/O problems in your attached storage and reports I/O wait time instead of just I/O counters. This lets you easily identify the resource that is actually being waited for and tune it instead of guessing by rules of thumb. Furthermore, you can associate the storage device with the applications and statements that are waiting on I/O.

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Performance problems caused by high I/O wait time may be tuned on the following levels:

• Oracle files. After finding Oracle files for which I/O wait time is high, you can improve I/O wait time using different techniques. For example, you can partition a table residing in the file, separate tables residing in the file into different files, or decrease the number of extents making up the file.
• Devices. After finding devices for which I/O wait time is high, you can improve I/O wait time using different techniques. For example, you can move a heavily used Oracle file to a less active device, change the configuration, and relocate devices with high waiting time to different physical devices or balance the volume of the disk directors.

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Precise is a Web-based application. You can access the Precise user interface using the Internet Explorer browser, version 6.0 or later. The syntax of the Precise URL address is: http://<server>:<port>, where <server> refers to the Precise FocalPoint server and <port> refers to the port number used by the GUI Web server. By default, the port number is 20790 (20760 for J2EE). For example: http://beanotown:20790.

This URL provides secure access to the StartPoint using authorized roles. From here, you can launch all Precise products. It gives you a quick overview of the status of your applications and access to the AdminPoint, where you can perform various management tasks (see the Precise Administration Guide for details).Note:

To launch your product using Precise StartPoint

1. Type the address of the StartPoint user interface into the Address bar of your browser and click Enter. The Precise login page opens. The login page provides secure access to Precise and to your specific product.
2. Specify your authorized role name and password. By default, both role name and password are admin. For more information about role names, see the Precise Administration Guide.
3. Click Login. The StartPoint page opens. This is the Precise home page.
4. On the Product Selection bar, from the drop-down list, select the product you want to launch.

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