Define Two or More Disk Journal Files
You must define at least two disk journal files when you journal to disk. When one journal file is full, CA IDMS/DB switches to another one. You must use an ARCHIVE JOURNAL utility statement to offload the full journal file.
Dynamic Allocation of Journal Files
Dynamic allocation of files is operating system and file-type dependent. For more information about dynamic file allocation in various operating systems, see 7.14.3, “Usage".
Archive Journal File Requirement
When you journal to disk journal files, you must also define at least one archive journal file to which CA IDMS/DB offloads the contents of a disk journal when it is full.
Incompatibility of Tape and Disk Journal Files
You cannot include the definition of a tape journal file in the DMCL if you include the definitions of disk and archive journal files.
Disk Journaling Used Under the Central Version
To take advantage of the automatic recovery and warmstart capabilities offered under the central version, you must journal to disk.
Disk Journals in Local Mode
A DMCL containing disk journals can be used in local mode but no journaling of database activity is performed. To journal in local mode, use a DMCL that defines a tape journal file instead.
Block size of Disk Journal File
The block size of a disk journal file is determined by the page size of the journal buffer. For VSAM disk journals, the page size of the journal buffer must be the control interval size of the disk journal.
The block size or control interval of the disk journal file must not be larger than the block size of the archive journal file.
Dataspaces Not Supported
The use of dataspaces for journal files is not supported.
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