Initialization Parameters
IBM® Connect:Direct® uses the following initialization parameters with the COPY statement checkpoint/restart facility:
| Parameter | Description |
|---|---|
| CKPT.MODE | Specifies whether the checkpoint function is performed when IBM Connect:Direct is transferring a file in
record mode or block mode. (Record mode transfer is used when reblocking of the output file is
specified.) It also specifies whether the checkpoint function is performed for partitioned data sets
and if so, what type. Automatic checkpointing of VSAM files is supported. This parameter does not apply to TCP/IP and LU6.2 connections. With TCP/IP and LU6.2 connections, checkpointing is based on the checkpoint interval requested (regardless of the data set type or whether it is in block or record format) and on both nodes' ability to perform the checkpoint function. When both nodes agree to do checkpointing, the checkpoint interval is controlled by the sending node while checkpoint record filing is done on the receiving node. |
| CKPT | Specifies the default interval for checkpointing when it is not specified on the
COPY statement. You should specify the CKPT value as a multiple of the value specified for the V2.BUFSIZE initialization parameter. If you do not, performance can seriously deteriorate. Note: Be aware of additional overhead associated with specifying too small a checkpoint interval, particularly when transferring large files. Note: For
sequential files, try to avoid using a CKPT value less than:
BLKSIZE * NCP * 10 where NCP is the number of buffers for reading data from or writing data to a sequential data set using BSAM For more information, search on Improving Performance in the IBM Sterling Connect:Direct for z/OS® Administration Guide. |
| CKPT.DAYS | Specifies the amount of time that checkpoint records are kept if they are not deleted. IBM Connect:Direct automatically deletes checkpoint records when a Process is restarted and runs to a successful completion. |
| CKPTDSN | Specifies the name of the checkpoint/restart file that holds checkpoint records during execution of the COPY statement. |
For detailed information about these parameters, search on Global Initialization Parameters in the IBM Sterling Connect:Direct for z/OS Administration Guide.