VTBUF

Use VTBUF to analyze buffer pool control blocks (BPCBs) and obtain a status summary for all buffer pools or a specific buffer pool. For each buffer pool, the following information is displayed:

Starting and ending address of buffer pools
Buffer pool address (BPCB)
Buffer type (fixed or pageable)
Buffer size
Number of buffers allocated
Slowdown threshold
Number of buffers available
Expansion threshold
Contraction threshold
Number of times expanded
Maximum number of buffers
Expansion increment
Expansion size
Percentage of buffers in use
Total number of buffers
Bytes in static and expanded areas
Buffers in other pools
Buffers in static area
Total queued request parameter headers (RPHs)

If any expansions have occurred, the pool extension block (PXB) address, number of buffers available, totals buffers, beginning of the extent, and the first available extent are also presented.

Operands

Buffer name: Enter a 2–7 character buffer name in the form cc or ccccBUF where cccc is the buffer name. Counts and totals information will be displayed in decimal form.
The default is ALL.

Equated symbol

Symbol: Description
buffername BSTART: Each starting buffer address
buffername BEND: Each ending buffer address

Note: For information on the DISPLAY BFRUSE (buffer use) command, which displays information about VTAM® buffer use, see z/OS Communications Server: SNA Operation.

Use the following syntax as an alternative to the panel interface.

Syntax


          .- --BUFFER--(--ALL--)--.   
>>-VTBUF--+-----------------------+----------------------------><
          '- --BUFFER--(--name--)-'

Sample output

VTBUF BUFFER(IO)
 
                             VTBUF Analysis
 
                        IO Buffer Analysis
 
Size of Buffers(bytes)          345   Buffer maximum                  110
Total buffers available          94   Static buffers allocated        110
Total number of buffers         110
Buffers in use (%)               15   Available static buffers         94
Bytes in static &
  expanded areas              37950
Slowdown threshold                5   Expansion threshold               6
Contraction threshold         32767
Number of expansions              0   Expansion increment              11
Expansion size                 4096
Total queued RPHs                 0
Fixed or pageable?       FIXED
Buffer pool address           X'028DB410'
Beginning address of pool     X'028F9000'
Ending address of pool        X'02903000'
Buffer pool has no extensions