This parameter is used to control the release of SAP Extended Memory for the operating system.
For more information see Release of SAP Memory for the Operating System.
The parameter specifies in seconds how long after the threshold specified in es/disclaim_threshold_MB has been exceeded when allocating a block held in the swap space, that this block is to be released for the OS.
A value of 0 means that this parameter is inactive. This is also the default setting.
Free blocks held in the swap space should be first read from the hard disk. But as the content is obsolete it is better for system performance to release this block for the OS and to request a new block from the main memory.