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You use the Shared Memory screen to view shared properties that are defined in the SAP Manufacturing Integration and Intelligence (SAP MII) Workbench. On this screen, you change or delete the current value of a shared property.

The existing default values of shared properties that are migrated with a project are not overwritten. To change the default value of a shared property, you must change it in the SAP MII Workbench.

Integration

You define shared properties for your project in the SharedProperties.mem file on the Meta-Inf tab page of the SAP MII Workbench. You define the default value for the property here.

Features

Following are few features of Shared Memory:

  • Active versus Design

    When the SharedProperties.mem file is configured, the property is set to be used. However, the value is not reflected in the active memory until the property is used.

  • Remove a property from active memory

    You can assign a null to the property through a link editor or delete the property using the Shared Memory admin UI. The following functions will clear the property from the defined links:

    • All types (as of 12.1 SP5 b35) - null

    • Numeric types: nullnumber

    • String : nullstring

    • Datetime: nulldate

    • Map/list: You can assign emptymap, emptylist to these properties to clear them out, but they can only be cleared through the admin UI.

  • Admin UI

    Allows you to see the active memory value for the shared properties. You can filter the properties by different projects. You can change/remove the active values by the following UI:

    • xMII 12.1 –   Data Services   Shared Memory  

    • MII 2.2 –   MII Workbench Administration screen   Tools  

  • Inline versus Persistent

    • Inline properties are stored in a hash map in server memory. Inline properties do not persist and are not recoverable after system restart.

      The hash map is not cluster safe by design. The map is used for quick storage and retrieval of values.

    • Persistent properties are stored in the XMII_DB_MEMORY table of the MII data source. It is cluster-safe and persists after system restart, but is slower as each storage or retrieval of values requires a call to the table.

  • Timeout

    • Timeout is a configurable parameter for each shared property. The default value is -1 for a property to sustain. If the timeout is defined, then the property will expire that many seconds after its last access. Once a property is stored or retrieved, the counter for the property expiration is reset.

    • A system thread, Shared Property Cleanup is available that runs once a minute to check the active memory properties for expiration. If expired, this thread will perform the cleanup.

  • Protected/Namespace

    Specifying a namespace helps to lock down properties for a specific folder within a project. A namespace can be configured as Project.Folder, and then only transactions from within that folder and subfolders will be able to access those variables.

  • Caching

    The caching indicator for shared properties indicate the default value of the property.

    • If the indicator is True/On, then the property has no default value. In other words, the property does not exist in active memory and if accessed, a null is returned.

    • If the indicator is False/Off, then the default value defined in the design time UI is returned and is set in the active memory.

Activities

To view or change the value of shared properties in the system, on the SAP MII administration menu, choose   Data Services   Shared Memory.