If availability of common service area (CSA) is a problem, you
should monitor the VTAM® buffer
pools for unused storage. You can do this with the DISPLAY BFRUSE
operator command or with the VTAM TYPE=SMS,ID=VTAMBUF
trace. The output from this trace goes to the generalized trace facility
(GTF).
The following example DISPLAY BFRUSE operator command report can be used to determine how
much CSA is not being used.
IST097I DISPLAY ACCEPTED
IST350I DISPLAY TYPE = BUFFER POOL DATA 860
IST920I IO00 BUFF SIZE 619 EXP INCREMENT 504
IST921I TIMES EXP 0 EXP/CONT THRESH 500 / *NA*
IST922I CURR TOTAL 4002 CURR AVAILABLE 4001
IST923I MAX TOTAL 4002 MAX USED 5
IST989I EXP LIMIT 696846 BUFFS REQUESTED 0
IST924I -------------------------------------------------------------
IST920I BS00 BUFF SIZE 260 EXP INCREMENT 70
IST921I TIMES EXP 0 EXP/CONT THRESH 29 / *NA*
IST922I CURR TOTAL 70 CURR AVAILABLE 70
IST923I MAX TOTAL 70 MAX USED 0
IST924I -------------------------------------------------------------
IST920I LP00 BUFF SIZE 2032 EXP INCREMENT 6
IST921I TIMES EXP 0 EXP/CONT THRESH 2 / *NA*
IST922I CURR TOTAL 12 CURR AVAILABLE 10
IST923I MAX TOTAL 12 MAX USED 4
IST924I -------------------------------------------------------------
IST920I XD00 BUFF SIZE 697 EXP INCREMENT 5
IST921I TIMES EXP 0 EXP/CONT THRESH 4 / *NA*
IST922I CURR TOTAL 5 CURR AVAILABLE 5
IST923I MAX TOTAL 5 MAX USED 0
IST924I -------------------------------------------------------------
IST920I LF00 BUFF SIZE 120 EXP INCREMENT 30
IST921I TIMES EXP 0 EXP/CONT THRESH 1 / *NA*
IST922I CURR TOTAL 30 CURR AVAILABLE 26
IST923I MAX TOTAL 30 MAX USED 4
IST924I -------------------------------------------------------------
IST920I CRPL BUFF SIZE 144 EXP INCREMENT 75
IST921I TIMES EXP 0 EXP/CONT THRESH 29 / *NA*
IST922I CURR TOTAL 75 CURR AVAILABLE 73
IST923I MAX TOTAL 75 MAX USED 2
IST924I -------------------------------------------------------------
IST920I SF00 BUFF SIZE 112 EXP INCREMENT 32
IST921I TIMES EXP 0 EXP/CONT THRESH 1 / *NA*
IST922I CURR TOTAL 32 CURR AVAILABLE 30
IST923I MAX TOTAL 32 MAX USED 2
IST924I -------------------------------------------------------------
IST920I SP00 BUFF SIZE 176 EXP INCREMENT 21
IST921I TIMES EXP 0 EXP/CONT THRESH 1 / *NA*
IST922I CURR TOTAL 21 CURR AVAILABLE 21
IST923I MAX TOTAL 21 MAX USED 0
IST924I -------------------------------------------------------------
IST920I AP00 BUFF SIZE 56 EXP INCREMENT 56
IST921I TIMES EXP 0 EXP/CONT THRESH 3 / *NA*
IST922I CURR TOTAL 56 CURR AVAILABLE 56
IST923I MAX TOTAL 56 MAX USED 0
IST924I -------------------------------------------------------------
IST920I TI00 BUFF SIZE 632 EXP INCREMENT 1002
IST921I TIMES EXP 0 EXP/CONT THRESH 60 / *NA*
IST922I CURR TOTAL 26004 CURR AVAILABLE 26004
IST923I MAX TOTAL 26004 MAX USED 5
IST924I -------------------------------------------------------------
IST920I T100 BUFF SIZE 1004 EXP INCREMENT 300
IST921I TIMES EXP 0 EXP/CONT THRESH 60 / *NA*
IST922I CURR TOTAL 500 CURR AVAILABLE 500
IST923I MAX TOTAL 500 MAX USED 0
IST924I -------------------------------------------------------------
IST920I T200 BUFF SIZE 2028 EXP INCREMENT 300
IST921I TIMES EXP 0 EXP/CONT THRESH 60 / *NA*
IST922I CURR TOTAL 9000 CURR AVAILABLE 9000
IST923I MAX TOTAL 9000 MAX USED 0
IST924I -------------------------------------------------------------
IST920I CRA4 BUFF SIZE 4080 EXP INCREMENT 10
IST921I TIMES EXP 0 EXP/CONT THRESH 20 / *NA*
IST922I CURR TOTAL 100 CURR AVAILABLE 98
IST923I MAX TOTAL 100 MAX USED 4
IST924I -------------------------------------------------------------
IST920I CRA8 BUFF SIZE 8176 EXP INCREMENT 6
IST921I TIMES EXP 0 EXP/CONT THRESH 2 / *NA*
IST922I CURR TOTAL 12 CURR AVAILABLE 11
IST923I MAX TOTAL 12 MAX USED 4
IST924I -------------------------------------------------------------
IST449I CSALIMIT = 464565K, CURRENT = 40695K, MAXIMUM = 40695K
IST790I MAXIMUM CSA USED = 40695K
IST1667I SYSTEM CSA LIMIT = 516184K
IST1831I 84% OF SYSTEM CSA STORAGE REMAINING = 433943K
IST449I CSA24 LIMIT = NOLIMIT, CURRENT = 59K, MAXIMUM = 59K
IST790I MAXIMUM CSA24 USED = 60K
IST595I IRNLIMIT = NOLIMIT, CURRENT = 0K, MAXIMUM = 0K
IST981I VTAM PRIVATE: CURRENT = 1352K, MAXIMUM USED = 1352K
IST924I -------------------------------------------------------------
IST2403I 64-BIT STORAGE TYPE CURRENT MAXIMUM LIMIT
IST2404I HVCOMMON 7M 7M NOLIMIT
IST2405I TRACE HVCOMMON 4M 4M 2048M
IST2413I PRIVATE 22M 22M NOLIMIT
IST2412I FIXED HVCOMMON 11M 11M NOLIMIT
IST2414I FIXED PRIVATE 22M 22M NOLIMIT
IST2415I TOTAL FIXED 33M 33M **NA**
IST924I -------------------------------------------------------------
IST1565I CSA MODULES = 1796K
IST1565I CSA24 MODULES = 40K
IST1565I PRIVATE MODULES = 7700K
IST314I END
The general formula for determining the amount of CSA not being
used for a given buffer pool follows:
NOTUSED = (MAXTOTAL - MAXUSED) x BUFFSIZE
Applying this formula to the I/O buffer pool shown in the sample
DISPLAY BFRUSE command report, the amount of CSA not being used follows:
IOBUF unused = (110 - 1) x 334 = 36,406 bytes of fixed CSA
The unused CSA for the other pools shown follows:
BSBUF unused = 7344 bytes of fixed CSA
LPBUF unused = 121920 bytes of pageable CSA
XDBUF unused = 6810 bytes of fixed CSA
LFBUF unused = 14160 bytes of fixed CSA
CRPL unused = 32960 bytes of pageable CSA
SFBUF unused = 6944 bytes of fixed CSA
SPBUF unused = 7200 bytes of pageable CSA
APBUF unused = 3136 bytes of fixed CSA
TIBUF unused = 37920 bytes of fixed CSA
CRA4 unused = 40800 bytes of pageable CSA
CRA8 unused = 98112 bytes of pageable CSA
Therefore, the conclusion is as follows:
TOTAL CSA unused = 406,512 bytes
TOTAL fixed = 112,720 bytes
As this example illustrates, this procedure can help you to identify
where CSA is not being used so that you can adjust your usage.
z/OS Communications Server: SNA Network Implementation Guide
Copyright IBM Corporation 1990, 2014