Statements and parameters for IVTPRM00

ECSA MAX
Defines the maximum amount of storage that is dedicated to ECSA CSM buffers.
maxecsa
A decimal integer that specifies the maximum bytes of ECSA storage that is dedicated to CSM use.
Value range: 1024 K to 2048 M
Default: The default value is 100 M
Notes:
  1. K indicates kilobytes; M indicates megabytes.
  2. You must code only one blank between the keywords ECSA and MAX. If more than one blank appears between these keywords, the system ignores the statement as a comment and no syntax error message is generated. In this case, the system uses the default value of 100 M.
  3. The ECSA MAX statement must be completed on one line.
  4. Do not code blanks between the keyword MAX and (.
FIXED MAX
Defines the maximum amount of storage that is dedicated to fixed CSM buffers.
maxfix
A decimal integer that specifies the maximum bytes of fixed storage that is dedicated to CSM use.
Value: The value range is 1024 K to 30720 M.
Default: Start of changeThe default is 200 M.End of change
Notes:
  1. K indicates kilobytes; M indicates megabytes.
  2. You must code only one blank between the keywords FIXED and MAX. If more than one blank appears between these keywords, the system ignores the statement as a comment and no syntax error message is generated. In this case, the system uses the default value of 100 M.
  3. The FIXED MAX statement must be completed on one line.
  4. Do not code blanks between the keyword MAX and (.
  5. Start of changeYou might want to specify a higher value for the FIXED MAX parameter if you are using a very high amount of HVCOMM storage buffers.End of change
Start of change
HVCOMM MAX
Defines the maximum amount of storage that is dedicated to High Virtual Common storage (Common storage above the bar) CSM buffers.
maxhvcomm
A decimal integer specifying the maximum bytes of High Virtual Common storage that is dedicated to CSM use.
Value range: 100 M to 999999 M
Default value: 2000 M
Notes:
  • M indicates megabytes.
  • Start of changeCode only one blank between the keywords HVCOMM and MAX. If more than one blank appears between these keywords, the system ignores the statement as a comment and no syntax error message is generated. In this case, the system uses the default value of 2000 M. End of change
  • The HVCOMM MAX statement must be completed in one line.
  • Do not code blanks between the keyword MAX and (.
End of change
POOL
One POOL definition can be specified for each CSM buffer pool of a particular bufsize and bufsource combination.
bufsize
The size of the buffers in the pool to be created.
Value range: 4 K, 16 K, 32 K, 60 K, 180 K
Default: None. A valid range value is required.
bufsource
The storage source from which buffers are allocated. The values are as follows:
DSPACE
Buffers are allocated from data space storage.
ECSA
Buffers are allocated from ECSA storage.
Start of changeHVCOMMEnd of change
Start of changeBuffers are allocated from High Virtual Common storage (common storage above the bar).End of change
expbuf
The number of free buffers by which the pool is expanded when the free buffers fall below the minfree value.
Value range: Start of changeFor ECSA and Data Space pools:End of change 
   Bufsize    Expbuf range
       4K     1 - 256
      16K     1 - 256
      32K     1 - 128
      60K     1 - 68
     180K     1 - 22
Start of changeFor HVCOMM pools:End of changeStart of change
   Bufsize    Expbuf range
       4K     1 - 1024
      16K     1 - 512
      32K     1 - 256
      60K     1 - 136
     180K     1 - 45
End of change
Note: Start of change CSM expands the HVCOMM buffer pool on a megabyte boundary. The above number is rounded to the number of buffers on the next megabyte of storage.End of change
Default: Start of changeNone.End of change
The IBM-supplied defaults for expbuf for all buffer pools are as follows:
Start of change
bufsize 4 K 16 K 32 K 60 K 180 K
ECSA 16 8 4 4 2
DSPACE 16 8 4 4 2
HVCOMM 256 64 32 17 5
End of change
initbuf
The initial number of buffers that are created in the pool when the first IVTCSM REQUEST=CREATE_POOL macro is issued by an application. If zero is specified, only the base pool structure is created and the pool is expanded on the first IVTSCSM REQUEST=GET_BUFFER based on the expbuf specification. The pool is not reduced below the level specified by either initbuf or expbuf, whichever is higher.
Value range: 0 - 9999
Default value: The IBM-supplied default value is used unless it is overridden by a CREATE_POOL request.
minfree
The minimum number of free buffers that are allowed in the pool at any time. The storage pool is expanded the value that is specified in expbuf if the number of free buffers falls below this limit.
Value range: 0 - 9999
Default: The IBM-supplied default value is used unless it is overridden by a CREATE_POOL request.
Parent topic: IVTPRM00 (Communication Storage Manager)