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GBLPAGFIL is a system parameter that defines the maximum number of systemwide pages allowed for global page-file sections (scratch global sections that can be used without being mapped to a file). These global page-file sections can be temporary, permanent, system, or group, and are allocated from the page file specified in the system process header at bootstrap time. When you allow pages for global page-file sections, you must increase the size of the page file accordingly. Users with CMKRNL privilege can change this parameter value on a running system.

Global page-file sections are created with the Create and Map Section system services ($CREATE_GPFILE, $CRMPSC, and $CRMPSC_ GPFILE_64) without an explicit disk file. These sections are used for the RMS global buffers required for shared files. Users of shared files should note that global page-file sections cause both the global page table and the default system page file (PAGEFILE.SYS) to be used. If the value of GBLPAGFIL is too small, $CRMPSC issues an error message when you attempt to create global page-file sections.

You must have scratch global sections if you use RMS global buffers. Each file using global buffers requires, in the system page file, the file's bucket size multiplied by the number of global buffers for that file. If the file's bucket size varies, as with RMS indexed files, use the maximum bucket size. For shared sequential files, use the multiblock count of the first stream to perform the $CONNECT service in place of the file's bucket size.