Red Hat 8.1 - Manual (Page 126)

WARNING
Setting this value will reduce data consistency and may lead to loss of data. This is because if
there is a power outage before the server can flush the batched transactions, those transactions
in the batch will be lost.
Do not set this value unless specifically requested to do so by Red Hat support.
If this attribute is not defined or is set to a value of 0, transaction batching will be turned off, and it will be
impossible to make remote modifications to this attribute via LDAP. However, setting this attribute to a
value greater than 0 causes the server to delay committing transactions until the number of queued
transactions is equal to the attribute value. A value greater than 0 also allows modifications to this
attribute remotely via LDAP. A value of 1 for this attribute allows modifications to the attribute setting
remotely via LDAP, but results in no batching behavior. A value of 1 at server startup is therefore useful
for maintaining normal durability while also allowing transaction batching to be turned on and off remotely
when desired. Remember that the value for this attribute may require modifying the nsslapd-db-
logbuf-size attribute to ensure sufficient log buffer size for accommodating the batched transactions.
NOTE
The nsslapd-db-transaction-batch-val attribute is only valid if the nsslapd-db-durable-
transaction attribute is set to on.
For more information on database transaction logging, refer to the "Monitoring Server and Database
Activity" chapter in the Directory Server Administrator's Guide.
Parameter Description
Entry DN cn=config, cn=ldbm database, cn=plugins,
cn=config
Valid Range 0 to 30
Default Value 0 (or turned off)
Syntax Integer
Example nsslapd-db-transaction-batch-val: 5
3.4 .1.18. nsslapd-db-trickle-percentage
This attribute sets that at least the specified percentage of pages in the shared-memory pool are clean
by writing dirty pages to their backing files. This is to ensure that a page is always available for reading
in new information without having to wait for a write.
Parameter Description
Entry DN cn=config, cn=ldbm database, cn=plugins,
cn=config
Valid Range 0 to 100
Default Value 40
Syntax Integer
Example nsslapd-db-trickle-percentage: 40
3.4 .1.19. nsslapd-db-verbose
This attribute specifies whether to record additional informational and debugging messages when
searching the log for checkpoints, doing deadlock detection, and performing recovery. This parameter is
meant for troubleshooting, and enabling the parameter may slow down the Directory Server.
Parameter Description
Entry DN cn=config, cn=ldbm database, cn=plugins,
cn=config
Valid Values on | off
Default Value off
Syntax DirectoryString
Example nsslapd-db-verbose: off
3.4 .1.20. nsslapd-dbncache
This attribute can split the LDBM cache into equally sized separate pieces of memory. It is possible to
specify caches that are large enough so that they cannot be allocated contiguously on some
architectures; for example, some systems limit the amount of memory that may be allocated contiguously
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Chapter 3. Plug-in Implemented Server Functionality Reference