From: Howard Chu Date: Fri, 26 Aug 2011 07:31:57 +0000 (-0700) Subject: mdb manpage X-Git-Url: https://git.sur5r.net/?p=openldap;a=commitdiff_plain;h=06d590fffe107ac75e59df83516501ee1f5e46e6 mdb manpage --- diff --git a/doc/man/man5/slapd-mdb.5 b/doc/man/man5/slapd-mdb.5 new file mode 100644 index 0000000000..92f5cd0734 --- /dev/null +++ b/doc/man/man5/slapd-mdb.5 @@ -0,0 +1,134 @@ +.TH SLAPD-MDB 5 "RELEASEDATE" "OpenLDAP LDVERSION" +.\" Copyright 2011 The OpenLDAP Foundation All Rights Reserved. +.\" Copying restrictions apply. See COPYRIGHT/LICENSE. +.\" $OpenLDAP$ +.SH NAME +slapd\-mdb \- Memory-Mapped DB backend to slapd +.SH SYNOPSIS +.B ETCDIR/slapd.conf +.SH DESCRIPTION +The \fBmdb\fP backend to +.BR slapd (8) +uses OpenLDAP's own Memory-Mapped DB (MDB) library to store data. +It relies completely on the underlying operating system for memory +management and does no caching of its own. +.LP +The \fBmdb\fP backend is similar to the \fBhdb\fP backend in that +it uses a hierarchical database layout which +supports subtree renames. It is both more space-efficient and more +execution-efficient than the \fBbdb\fP backend, while being overall +much simpler to manage. +.SH CONFIGURATION +These +.B slapd.conf +options apply to the \fBmdb\fP backend database. +That is, they must follow a "database mdb" line and +come before any subsequent "backend" or "database" lines. +Other database options are described in the +.BR slapd.conf (5) +manual page. +.TP +.BI checkpoint \ \ +Specify the frequency for flushing the database disk buffers. +This setting is only needed if the \fBdbnosync\fP option is used. +Note: this feature is not yet implemented. +The checkpoint will occur if either \fI\fP data has been written or +\fI\fP minutes have passed since the last checkpoint. +Both arguments default to zero, in which case they are ignored. When +the \fI\fP argument is non-zero, an internal task will run every +\fI\fP minutes to perform the checkpoint. +.TP +.B dbnosync +Specify that on-disk database contents should not be immediately +synchronized with in memory changes. +Enabling this option may improve performance at the expense of data +security. By default, a full data flush/sync is performed when each +transaction is committed. +.TP +.BI directory \ +Specify the directory where the MDB files containing this database and +associated indexes live. +A separate directory must be specified for each database. +The default is +.BR LOCALSTATEDIR/openldap\-data . +.TP +\fBindex \fR{\fI\fR|\fBdefault\fR} [\fBpres\fR,\fBeq\fR,\fBapprox\fR,\fBsub\fR,\fI\fR] +Specify the indexes to maintain for the given attribute (or +list of attributes). +Some attributes only support a subset of indexes. +If only an \fI\fP is given, the indices specified for \fBdefault\fR +are maintained. +Note that setting a default does not imply that all attributes will be +indexed. Also, for best performance, an +.B eq +index should always be configured for the +.B objectClass +attribute. + +A number of special index parameters may be specified. +The index type +.B sub +can be decomposed into +.BR subinitial , +.BR subany ,\ and +.B subfinal +indices. +The special type +.B nolang +may be specified to disallow use of this index by language subtypes. +The special type +.B nosubtypes +may be specified to disallow use of this index by named subtypes. +Note: changing \fBindex\fP settings in +.BR slapd.conf (5) +requires rebuilding indices, see +.BR slapindex (8); +changing \fBindex\fP settings +dynamically by LDAPModifying "cn=config" automatically causes rebuilding +of the indices online in a background task. +.TP +.BI maxsize \ +Specify the maximum size of the database in bytes. A memory map of this +size is allocated at startup time and the database will not be allowed +to grow beyond this size. The default is 10487560 bytes. This setting +may be changed upward if the configured limit needs to be increased. +.TP +.BI mode \ +Specify the file protection mode that newly created database +files should have. +The default is 0600. +.TP +.BI searchstack \ +Specify the depth of the stack used for search filter evaluation. +Search filters are evaluated on a stack to accommodate nested AND / OR +clauses. An individual stack is assigned to each server thread. +The depth of the stack determines how complex a filter can be +evaluated without requiring any additional memory allocation. Filters that +are nested deeper than the search stack depth will cause a separate +stack to be allocated for that particular search operation. These +allocations can have a major negative impact on server performance, +but specifying too much stack will also consume a great deal of memory. +Each search stack uses 512K bytes per level. The default stack depth +is 16, thus 8MB per thread is used. +.SH ACCESS CONTROL +The +.B mdb +backend honors access control semantics as indicated in +.BR slapd.access (5). +.SH FILES +.TP +.B ETCDIR/slapd.conf +default +.B slapd +configuration file +.SH SEE ALSO +.BR slapd.conf (5), +.BR slapd\-config (5), +.BR slapd (8), +.BR slapadd (8), +.BR slapcat (8), +.BR slapindex (8), +OpenLDAP MDB documentation. +.SH ACKNOWLEDGEMENTS +.so ../Project +Written by Howard Chu.