IBM Support

What is the function of the ISTSVF subpool?

Technote (FAQ)


The 'GETVIS SVA,ALL' command shows the ISTSVF subpool. What is the ISTSVF subpool used for?.


In this sample output from the GETVIS SVA,ALL command,

GETVIS SVA,ALL                                                          
AR 0015 GETVIS USAGE   SVA-24    SVA-ANY                    SVA-24    SV
AR 0015  AREA SIZE:    3,556K    14,968K                                
AR 0015  USED AREA:    3,452K     9,004K MAX. EVER USED:    3,556K    10
AR 0015  FREE AREA:      104K     5,964K LARGEST FREE:         20K     4
AR 0015 SUMMARY REPORT                                                  
AR 0015 SUBPOOL       REQUEST  <--SVA-24-AREA---    --SVA-ANY-AREA-->  
AR 0015 Default                            1,552K                  44K  
AR 0015 ISTSVF                               896K               1,884K  

ISTSVF is the SVA (Shared Virtual Area) subpool used by VTAM for I/O Buffers (IOBUF) In z/VSE. You can move this subpool to 31-bit SVA by setting IOBUF31=YES in the VTAM start options list.

IST is the prefix for VTAM, SV stands for SVA and F stands for fixed

Document information

More support for: VTAM for VSE/ESA and VM/ESA

Software version: 4.2

Operating system(s): z/VSE

Reference #: 1366870

Modified date: 21 February 2013