GDSX (Extended General Device Support) Manual

Design and Development
Extended General Device Support (GDSX) Manual—529931-001
2-60
MAXBUFPOOL
looptime ticks without transferring control, it is presumed to be in a loop and is
suspended with a fault.
MAXBUFPOOL
This static parameter can be used to specify the maximum size of the extended buffer
pool.
If the size specified for the extended buffer pool is too large, error message 10002 is
sent to the home terminal:
10002 maxTCBpool or Buffer/Msg pool too large
MAXCPSIZE
This static parameter determines the size of the buffer sent when USCODE does a
checkpoint to the backup process. This buffer is in the extended segment for control
structures. See Space Usages and Limitations on page 2-19.
The Q^CP procedure moves local memory global data within a user’s named or private
global data block to the checkpoint buffer. The Q^CPX procedure moves extended
memory data to the checkpoint buffer. Up to four data areas can be moved to the
checkpoint buffer with a single call to Q^CP[X]. Multiple calls to Q^CP[X] can be done
before calling DO^CP or ^CHECKPOINT. Q^CP[X] queues data until the data in the
checkpoint buffer, of the word size specified by MAXCPSIZE, including three control
words per data area copied, exceeds the size of MAXCPSIZE.
If the checkpoint buffer overflows during a call to Q^CP[X] from the USER^BACKUP
exit, TSCODE automatically writes the current checkpoint buffer to the backup
process.
TSCODE ensures that MAXCPSIZE is at least the size of TASKCPSIZE.
Internal DEFINE Name CONFIG^PARAMS Name Default Value Range
looptime loop^time 200 ticks 0–32,767 ticks
Internal DEFINE Name CONFIG^PARAMS Name Default Value Range
maxbufpoolsize maxbufpool^size 32K bytes Up to 7.5
megabytes
Internal DEFINE Name CONFIG^PARAMS Name Default Value Range
max^cp^wds max^chkpt^wds 4096 words 512–16,364
words
Caution. If the checkpoint buffer overflows during a call to Q^CP[X] from a user exit other than
USER^BACKUP, the backup process will be terminated and Q^CP[X] will return 0. To prevent
this, ensure that MAXCPSIZE is large enough. If the backup process is terminated, it is still
the caller’s responsibility to release the semaphore by means of GIVE^CPSEM.