Guardian Programming Reference Summary for pTAL and TAL

SETMODE Operations
Guardian Programming Reference Summary for pTAL and TAL—522631-001
11-18
91 Disk: Set cache and sequential option (Function 91 is not applicable for
alternate-key files.)
param1
= 0 system managed (default).
DP2 will detect sequential access; when detected, it will set LRU access to
sequential and perform key-sequenced sequential splits.
= 1 direct I/O, bypass disk cache.
= 2 random access, LRU-chain buffer.
= 3 sequential access, reuse buffer. Directs DP2 to set cache.
LRU access to sequential and perform key-sequenced sequential splits.
The param2 parameter is not used with function 91.
Sequential LRU access results in “random” LRU chaining that provides an
approximate half-life within the LRU cache chain.
Key-sequenced sequential splits attempt to leave the inserted record as the last
in the old block, in contrast to a 50/50 split. This helps to ensure a compact
key-sequenced structure when multiple sequential records are inserted.
92 Disk: Set maximum number of extents for a nonpartitioned file. (Function 92 is
invalid for audit-trail files and for partitioned non-key-sequenced files.)
The param1 parameter specifies the new maximum number of extents value.
There is no guarantee of success if you specify a value greater than 500. The
default is 16 extents.
The param2 parameter is not used with function 92.
This function operates only on Guardian objects. If an OSS file is specified,
file-system error 2 occurs.
93 Disk: Set buffer length for an unstructured file
param1=new BUFFERSIZE value, must be valid DP2 block size. Valid DP2
block sizes are 512,1024, 2048, 4096 bytes (the default is 4096 bytes).
The param2 parameter is not used with function 93.
This function operates only on Guardian objects. If an OSS file is specified,
file-system error 2 occurs.
94 Disk: Set audit-checkpoint compression option for an Enscribe file.
param1
= 0 no audit-checkpoint compression (default)
= 1 audit-checkpoint compression enabled
param2
= 0 change the open option setting of the audit-checkpoint compression option
(default).
= 1 change the file label default value of the audit-checkpoint compression
option.
<function> Parameters and Effect