Maxsegratio; Maxwhthreads; Minpartsize; [No]Byindex - SAS Scalable Performance Data Server 4.5 Administrator's Manual

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Chapter 11 • Setting Up SPD Server Parameter Files
Usage
MAXGENNUM=<ldap_server_binddn_string> <maximum-number-of-member-tables> ;

MAXSEGRATIO=

controls segment candidate pre-evaluation for WHERE clause predicates with a hybrid
index. The WHERE clause planner pre-evaluates the segment candidates for the predicate.
Only the segment candidates are searched to resolve the WHERE clause. Some queries can
benefit from no pre-evaluation, based on the ratio of the number of segments containing
candidates, to the total number of segments in the file. If the percentage of possible
segments exceeds the specified value, pre-evaluation is not performed and all of the
segments are searched to resolve the WHERE clause. If a value is not specified, the default
value is 75 percent.
Usage
MAXSEGRATIO=<ldap_server_binddn_string> <maximum-ratio-of-segment-candidates-to-segments>

MAXWHTHREADS=

specifies the number of parallel threads to launch for a WHERE clause evaluation.
Usage
MAXWHRTHREADS=<ldap_server_binddn_string> <maximum-number-of-parallel-threads> ;

MINPARTSIZE=

ensures that large SPD Server tables cannot be created with arbitrarily small partition size.
Large SPD Server tables with small partition sizes create an excessive number of physical
files, which increases clutter and degrades I/O performance. The default value for
MINPARTSIZE= is 16 MB. The most common values for the MINPARTSIZE parameter
range from 128 MB to 256 MB.
Usage
MINPARTSIZE=<ldap_server_binddn_string> <minimum-partition-size> ;

[NO]BYINDEX

Controls whether to use an index for a BY-sort. The default is NOBYINDEX, which does
not allow use of the index. The [NO]BYINDEX server parameter is used only when the
SPDSNBIX= macro is set to NO (default value).
Usage
BYINDEX ; NOBYINDEX ;

[NO]COREFILE

controls whether the LIBNAME proxy creates a core file in the event of an unexpected
process trap. The default value is NOCOREFILE.
Usage
COREFILE ; NOCOREFILE ;