Red Hat 8.1 - Manual (Page 127)

by a process. If nsslapd-dbncache is 0 or 1, the cache will be allocated contiguously in memory. If it is
greater than 1, the cache will be broken up into ncache, equally sized separate pieces of memory.
To configure a dbcache size larger than 4 gigabytes, add the nsslapd-dbncache attribute to
cn=config, cn=ldbm database, cn=plugins, cn=config between the nsslapd-
dbcachesize and nsslapd-db-logdirectory attribute lines.
Set this value to an integer that is one-quarter (1/4) the amount of memory in gigabytes. For example, for
a 12 gigabyte system, set the nsslapd-dbncache value to 3; for an 8 gigabyte system, set it to 2.
This attribute is provided only for system modification/diagnostics and should be changed only with the
guidance of Red Hat technical support or Red Hat professional services. Inconsistent settings of this
attribute and other configuration attributes may cause the Directory Server to be unstable.
The server has to be restarted for changes to this attribute to go into effect.
Parameter Description
Entry DN cn=config, cn=ldbm database, cn=plugins,
cn=config
Valid Values 1 to 4
Default Value 1
Syntax Integer
Example nsslapd-dbncache: 1
3.4 .1.21. nsslapd-directory
This attribute specifies absolute path to database instance. If the database instance is manually created
then this attribute must be included, something which is set by default (and modifiable) in the Directory
Server Console. Once the database instance is created, do not modify this path as any changes risk
preventing the server from accessing data.
Parameter Description
Entry DN cn=config, cn=ldbm database, cn=plugins,
cn=config
Valid Values Any valid absolute path to the database instance
Default Value
Syntax
DirectoryString
Example nsslapd-directory:
/var/lib/dirsrv/slapd-instance_name/db
3.4 .1.22. nsslapd-import-cachesize
This performance tuning-related attribute determines the size, in bytes, of the database cache used in
the bulk import process. Setting this attribute value so that the maximum available system physical
memory is used for the database cache during bulk importing optimizes bulk import speed. Attempting to
set a value that is not a number or is too big for a 32-bit signed integer returns an
LDAP_UNWILLING_T O_PERFORM error message, with additional error information explaining the
problem.
NOTE
A cache is created for each load that occurs. For example, if the user sets the nsslapd-import-
cachesize attribute to 1 gigabyte, then 1 gigabyte is used when loading one database, 2
gigabytes is used when loading two databases, and so on. Ensure there is sufficient physical
memory to prevent swapping from occurring, as this would result in performance degradation.
Parameter Description
Entry DN cn=config, cn=ldbm database, cn=plugins,
cn=config
Valid Range 500 kilobytes to 4 gigabytes for 32-bit platforms
and 500 kilobytes to 2^64-1 for 64-bit platforms
Default Value 20000000
Syntax Integer
Example nsslapd-import-cachesize: 20000000
3.4 .1.23. nsslapd-import-cache-autosize
This performance tuning-related attribute automatically sets the size of the import cache
(importCache) to be used during the command-line-based import process of LDIF files to the
Red Hat Directory Server 8.1 Configuration and Command Reference
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