Technical data
Programming Features
5.6 Large Page-File Sections (Alpha)
$ SHOW MEMORY/FILES
System Memory Resources on 22-MAY-2000 19:04:19.67
Swap File Usage (8KB pages): Index
!
Free Size
DISK$ALPHASYS:[SYS48.SYSEXE]SWAPFILE.SYS
1 904 904
DISK$SWAP:[SYS48.SYSEXE]SWAPFILE.SYS;1
2 1048 1048
Total size of all swap files: 1952
Paging File Usage (8KB pages): Index
"
Free Size
DISK$PAGE:[SYS48.SYSEXE]PAGEFILE.SYS;1
253 16888 16888
DISK$ALPHASYS:[SYS48.SYSEXE]PAGEFILE.SYS
254 16888 16888
Total size of all paging files: 33776
Total committed paging file usage:
#
1964
! Number of swap files. Begins with an index value of 1 and increases in
count.
" Number of page files. Begins with an index value of 254 and decreases in
count.
# Total committed page file usage. As in previous releases, more pages can
reside in page-file sections systemwide than would fit into installed page
files.
• The SHOW MEMORY/FILES/FULL display no longer contains separate
usage information for page and swap files. Because page-file information
is no longer reserved, the system does not need to maintain the number of
processes interested in a distinct page or swap file. For example:
$ SHOW MEMORY/FILES/FULL
System Memory Resources on 22-MAY-2000 18:47:10.21
Swap File Usage (8KB pages): Index Free Size
DISK$ALPHASYS:[SYS48.SYSEXE]SWAPFILE.SYS
1 904 904
Paging File Usage (8KB pages): Index Free Size
DISK$ALPHASYS:[SYS48.SYSEXE]PAGEFILE.SYS
254 16888 16888
Total committed paging file usage: 1960
• System parameters PAGFILCNT and SWPFILCNT are now obsolete. Up to
254 page and swap files can be installed.
5.7 Multipath System Services
The new Multipath system services provide the capability to return path
information and allow you to enable, disable, and switch specific I/O paths to any
device.
The concept of multiple I/O paths to storage devices was introduced in OpenVMS
Version 7.2-1. It is now possible to select more than one I/O path to a device in
the event that the path in use should fail.
To assist in decision making when configuring a system’s I/O structure, the
following DCL commands were made available to allow you to display I/O path
information and change the current settings affecting these paths:
• SET DEVICE device-name/PATH=path-description-string/SWITCH
5–6 Programming Features