7.7.5.31 DESCRIBE XRMEMCACHECONTENT

Purpose

The DESCRIBE XRMEMCACHECONTENT command displays a list of attributes for the XRMEMCACHECONTENT object type.

Syntax

DESCRIBE XRMEMCACHECONTENT

Usage Notes

The attributes displayed by the DESCRIBE XRMEMCACHECONTENT command can include:

  • cachedKeepSize: Size, in bytes, cached in keep mode for this object.

  • cachedSize: Size, in bytes, cached for this object.

  • cachedWriteSize: Size, in bytes, of cached data for this object in XRMEM cache cache that has not yet been written to hard disk.

  • clusterName: Name of the cluster associated with the cache object.

  • columnarCacheSize: Size, in bytes, cached in Hybrid Columnar Compression (HCC) format for this object.

  • columnarKeepSize: Size, in bytes, cached in Hybrid Columnar Compression (HCC) format that is in keep mode for this object.

  • dbID: Database unique name identifier.

  • dbUniqueName: Database unique name.

  • hitCount: Number of I/Os which read data from XRMEM cache for this object.

  • missCount: Number of I/Os which read data from disk for this object.

  • objectNumber: Mostly specifies the Oracle Database dictionary object number of the database object (table, index, partition, and so on) that is associated with the XRMEMCACHECONTENT object.

    Additionally, the following values have special meaning:

    • 0 (zero) indicates that the object number is undefined. This value is often used in conjunction with internal I/O performed by ASM.
    • 4294967292 indicates that the XRMEMCACHECONTENT object contains ASM Dynamic Volume Manager (ADVM) data.

    • 4294967293 indicates cached redo log data.

    • 4294967294 and 4294967295 indicate data from internal database objects, such as temporary segments, rollback segments, control file data, and so on, which is not associated with a specific data object (table, index, partition, and so on).

  • tableSpaceNumber: Tablespace number associated with the database object.

  • vaultID: Exascale vault identifier associated with the cache object.

Examples

The following example shows the DESCRIBE command with the XRMEMCACHECONTENT object.

Example 7-124 Describing the XRMEMCACHECONTENT Object

CellCLI> DESCRIBE XRMEMCACHECONTENT

         cachedKeepSize
         cachedSize
         cachedWriteSize
         clusterName
         columnarCacheSize
         columnarKeepSize
         dbID
         dbUniqueName
         hitCount
         missCount
         objectNumber
         tableSpaceNumber
         vaultID