OLAP: Cache Monitor (SAP Library - Performance Optimization)

OLAP: Cache Monitor

Purpose

On the Cache Monitor screen you can get information on the global cache parameters, the amount of memory used by the query runtime objects and the current underlying cache structure.

Integration

You access the OLAP Cache Monitor (transaction RSRCACHE) from the SAP Easy Access screen, from Business Explorer ® BEx Monitor ® OLAP: Cache Monitor. From the Query Monitor screen, you can get to the OLAP Cache Monitor via This graphic is explained in the accompanying text Cache Monitor.

Settings for the global cache parameters are made in Customizing (see Global Cache Parameters).

The cache-relevant settings that were set for an InfoProvider or query can “overwrite” the global cache parameters.

· You can set the standard cache mode for an InfoProvider in Customizing. If you change these settings later the changes do not affect existing queries for this InfoProvider but only take effect for future queries created for this InfoProvider.

· You can change the cache mode for a query in the Query Monitor screen (see Query Properties).

Note

You can access an overview of the cache-relevant data for a query (for example, important time stamps) from the Query Monitor screen via This graphic is explained in the accompanying text Technical Info (see Technical Information).

Features

By clicking the pushbutton on the left-hand side of the screen, you are able to select which information is displayed in the right-hand screen area. You have the following options:

Cache parameters

Display global cache parameters. The display is based on the settings made in Customizing. Example:

	Cache Parameters
	Cache active
	Local cache size	100 MB
	Global cache size	200 MB
	Cache persistence mode	Cluster table

If you want to change any settings, choose This graphic is explained in the accompanying text Cache Parameter.You can find further information under Global Cache Parameters.

Note

You can find additional information on the system valuations specified in the first column under Technical Information.

Cache mode functions

The following functions are arranged in relation to the different cache modes (see Cache Mode).

This graphic is explained in the accompanying text Main Memory for the cache modes Main Memory Cache With/ Without Swapping

Pushbutton	Display
Technical Info	Cache-relevant register code for the query run-time objects displayed, buffer status displayed (Shared Memory)
Buffer Objects Hierarchical Display or Buffer Objects List Display	Buffer objects displayed

Note

You will find additional information under Cache Data Removal and Swapping.

This graphic is explained in the accompanying text AppServer Flat file | Cluster | Blob for cache mode Persistent Cache pro Application Server

Pushbutton	Display
Technical Info	Cache-relevant register code for the query runtime objects displayed
Buffer Objects Hierarchical Display or Buffer Objects List Display	Buffer objects displayed

This graphic is explained in the accompanying text Cross-AppServer Flat file | Cluster | Blob for cache mode Persistent Cache Cross-Application Server

Pushbutton	Display
Technical Info	Cache-relevant register code for the query runtime objects displayed
Buffer Objects Hierarchical Display or Buffer Objects List Display	Buffer objects displayed

Note

You can choose from the following display modes for buffer objects:

This graphic is explained in the accompanying text Buffer Objects Hierarchical Display

This graphic is explained in the accompanying text Buffer Objects List Display

The default setting is to display buffer objects in a hierarchically structured query directory. You can find additional information under Cache Structure.

Toolbar functions

The following functions are available in the screen toolbar:

General functions

Function	What you need to know
(Refresh)
(Delete)	Deletes the cached data in accordance with the cache mode selected. That means that those buffer objects that you chose to display are deleted. If no selection has been made the system does not delete any data. This function is useful when testing
Cache Parameter	See Global Cache Parameters.

Functions for the cache mode Main Memory Cache with/ Without Swapping

Function

What you need to know

This graphic is explained in the accompanying text Buffer Monitor

Choose This graphic is explained in the accompanying text Buffer Monitor or Buffer Overview to check, for example, whether enough cache memory is available.

You can use This graphic is explained in the accompanying text Buffer Monitor to arrive at the Buffer Monitoring Tool screen, which gives you can overview of the buffer for your application server. In the Buffer Overview screen area the shared memory rows (buffer: Exp/ImpMem) contain data relevant to the OLAP cache:

· Size: Maximum size of the cache memory in bytes

· Free bytes: Free cache memory in bytes

· Directory: Maximum number of directories, that is, individual packages in the cache memory

· Dir. Free: Number of free directories

· Efficiency: Degree to which requests can be met, in %, - corresponds to the Hit ratio in the Buffer Overview

This graphic is explained in the accompanying text Buffer Overview

The Tune Summary screen appears (transaction ST02). The shared memory row (buffer: Exp/Imp SHM) contains data relevant to the OLAP cache:

· Hit ratio: [%] - corresponds to Efficiency in the Buffer Monitor

· Allocated: [kB]

· Free space: [kB] and [%]

· Dir. size: Entries

· Free directory: Entries and [%]

Caution

Note that both the number of bytes and the number of directories have a limiting effect. You can find out which of these sizes may be critical from the relationship between the respective maximum value and free capacity value.

Note

You will find additional information under Structure link The Buffer Monitor

Functions for the cache modes Main Memory Cache with Swapping (into a file), and the persistence mode with Flat File Cache

Function

What you need to know

This graphic is explained in the accompanying text Logical File Name

See Logical File Names (transaction FILE).

This graphic is explained in the accompanying text Directory Overview

The SAP Directories screen appears.

Example

DIR_GLOBAL /usr/<SYSID>/global

Double-click on the physical path to get to the file display. If you have kept to the naming conventions, you can find your physical file under CACHE_<HOST>_<SYSID>_<PARAM_1> or CACHE_<SYSID>_<PARAM_1>.

Further information about defining logical and physical file paths and –names can be found under Logical File Names.