IBM Mainframe Discussion List <[email protected]> wrote on 03/02/2009
06:28:55 PM:
> 90 XXH99NMODF DD SUBSYS=('BLSR','DDNAME=BLSRMODF', *MOD FILE *
> XX 'BUFSI=4096,BUFSD=8192',
> CISIZES --------------1536 ------4096
> DATA CI/CA----------------180
> KEYLEN---------------------14
> XX 'BUFNI=7972,BUFND=272',
> XX 'RMODE31=ALL','MSG=I',
> XX 'SHRPOOL=01')
> 91 XXBLSRMODF DD DSN=&V1..HBBMA.YW&PL.MODS, * MODIFIER FILE *
> XX DISP=(SHR,KEEP,KEEP)
> IEFC653I SUBSTITUTION JCL - [email protected],DISP=(
> 92 XXH99NPFLG DD SUBSYS=('BLSR','DDNAME=BLSRPFLG', *PFLG FILE *
> XX 'BUFSI=4096,BUFSD=8192',
> CISIZES --------------1536 ------4096
> DATA CI/CA----------------180
> KEYLEN-----------------8
> XX 'BUFNI=4070,BUFND=532',
> XX 'RMODE31=ALL','MSG=I',
> XX 'SHRPOOL=01')
> 93 XXBLSRPFLG DD DSN=&V1..HBBMA.MW&PL.PFLG&NODE, *PROC STUB FILE*
> XX DISP=(SHR,KEEP,KEEP)
> IEFC653I SUBSTITUTION JCL - [email protected],DISP=(
>
> Note that the JCL above is TEST and that the files are small but the
values
> are intended for PROD volumes.
>
> Since the two data sets are the only ones that have SHRPOOL=01 we
consider
> them together as a start. All the others default to SHRPOOL=0.
> As they are both have INDEX ----1536 and DATA ---4096 CISIZES, I do not
> understand the use of 'BUFSI=4096,BUFSD=8192'. It would seem that
> (4096 - 1536) = 2560 bytes = 62% of each INDEX and
> (8192 - 4096) = 4096 bytes = 50% of each DATA buffer is unusable and
thus a
> total waste.
>
> Assuming that the BUFNI/BUFND requests for each SHRPOOL are cumulative
> BUFNI=7972 and BUFNI=4070 together request 12038 buffers for the INDEX
SET,
> plus ONE SEQUENCE SET CI and ONE reserved CI for splits, even if the
data
> set is opened INPUT.
For a particular SHRPOOL Id, nothing is cumulative. When the first
OPEN occurs for a specific SHRPOOL Id, BLSR creates the pool. If another
OPEN is done specifying the same SHRPOOL Id, the already created pool is
used, and the BUF* and RMODE parameters are irrelevant.
Jim Mulder z/OS System Test IBM Corp. Poughkeepsie, NY
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [email protected] with the message: GET IBM-MAIN INFO
Search the archives at http://bama.ua.edu/archives/ibm-main.html
