Server User Manual

Database Attributes under cn=config, cn=ldbm database, cn=plugins, cn=config
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In Directory Server, the import operation can be run as a server task or exclusively on the command-
line. In the task mode, the import operation runs as a general Directory Server operation. The
nsslapd-import-cache-autosize attribute enables the import cache to be set automatically to
a predetermined size when the import operation is run on the command-line. The attribute can also
be used by Directory Server during the task mode import for allocating a specified percentage of free
memory for import cache.
By default, the nsslapd-import-cache-autosize attribute is enabled and is set to a value of -1.
This value autosizes the import cache for the ldif2db operation only, automatically allocating fifty
percent (50%) of the free physical memory for the import cache. The percentage value (50%) is hard-
coded and cannot be changed.
Setting the attribute value to 50 (nsslapd-import-cache-autosize: 50) has the same effect
on performance during an ldif2db operation. However, such a setting will have the same effect on
performance when the import operation is run as a Directory Server task. The -1 value autosizes
the import cache just for the ldif2db operation and not for any, including import, general Directory
Server tasks.
NOTE
The purpose of a -1 setting is to enable the ldif2db operation to benefit from free
physical memory but, at the same time, not compete for valuable memory with the
entry cache, which is used for general operations of the Directory Server.
Setting the nsslapd-import-cache-autosize attribute value to 0 turns off the import cache
autosizing feature - that is, no autosizing occurs during either mode of the import operation. Instead,
Directory Server uses the nsslapd-import-cachesize attribute for import cache size, with a
default value of 20000000.
There are three caches in the context of Directory Server: database cache, entry cache, and import
cache. The import cache is only used during the import operation. The nsslapd-cache-autosize
attribute, which is used for autosizing the entry cache and database cache, is used during the
Directory Server operations only and not during the ldif2db command-line operation; the attribute
value is the percentage of free physical memory to be allocated for the entry cache and database
cache.
If both the autosizing attributes, nsslapd-cache-autosize and nsslapd-import-cache-
autosize, are enabled, ensure that their sum is less than 100.
Parameter Description
Entry DN cn=config, cn=ldbm database, cn=plugins,
cn=config
Valid Range -1, 0 (turns import cache autosizing off) to 100
Default Value -1 (turns import cache autosizing on for ldif2db
only and allocates 50% of the free physical
memory to import cache)
Syntax Integer
Example nsslapd-import-cache-autosize: -1