Functional differences between UPAM and FASTPAM

• FASTPAM can only be used to process PAM files with the following file attributes:

  • BLOCK-CONTROL-INFO=*NO or *DATA

  • BUFFER-LENGTH = *STD(2n), n=1,2...8

• The following functions are not supported by FASTPAM:

  • DUMMY files

  • tape processing

  • RFA

• FASTPAM supports synchronous and asynchronous read and write operations. The following operations are offered by UPAM, but are not supported by FASTPAM:

  • CHK

  • LOCK / UNLOCK

  • LRD / LRDWT / WRTWU

  • SETL

  • SYNC

• FASTPAM can handle I/Os in data spaces.

• The functionality of the UPAM operation SETLPP is included in the framework of FASTPAM CLOSE processing.

• The function SHARUPD=*WEAK is not supported (see also "Multi-user mode").

• An implicit WAIT is not possible.

• Within an OPEN / CLOSE bracket, asynchronous I/Os can either be terminated only by WAIT, or their termination can be reported only via the eventing mechanism.

• It is not possible to specify a relative page number.