.TH SLAPD-MDB 5 "RELEASEDATE" "OpenLDAP LDVERSION"
-.\" Copyright 2011-2012 The OpenLDAP Foundation All Rights Reserved.
+.\" Copyright 2011-2013 The OpenLDAP Foundation All Rights Reserved.
.\" Copying restrictions apply. See COPYRIGHT/LICENSE.
.\" $OpenLDAP$
.SH NAME
.SH DESCRIPTION
The \fBmdb\fP backend to
.BR slapd (8)
-uses OpenLDAP's own Memory-Mapped DB (MDB) library to store data.
+uses OpenLDAP's Lightning Memory-Mapped DB (LMDB) library to store data.
It relies completely on the underlying operating system for memory
management and does no caching of its own.
.LP
transaction is committed.
.TP
.BI directory \ <directory>
-Specify the directory where the MDB files containing this database and
+Specify the directory where the LMDB 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
+\fBenvflags \fR{\fBnosync\fR,\fBnometasync\fR,\fBwritemap\fR,\fBmapasync\fR,\fBnordahead\fR}
+Specify flags for finer-grained control of the LMDB library's operation.
+.RS
+.TP
+.B nosync
+This is exactly the same as the
+.I dbnosync
+directive.
+.RE
+.RS
+.TP
+.B nometasync
+Flush the data on a commit, but skip the sync of the meta page. This mode is
+slightly faster than doing a full sync, but can potentially lose the last
+committed transaction if the operating system crashes. If both
+.I nometasync
+and
+.I nosync
+are set, the
+.I nosync
+flag takes precedence.
+.RE
+.RS
+.TP
+.B writemap
+Use a writable memory map instead of just read-only. This speeds up write operations
+but makes the database vulnerable to corruption in case any bugs in slapd
+cause stray writes into the mmap region.
+.RE
+.RS
+.TP
+.B mapasync
+When using a writable memory map and performing flushes on each commit, use an
+asynchronous flush instead of a synchronous flush (the default). This option
+has no effect if
+.I writemap
+has not been set. It also has no effect if
+.I nosync
+is set.
+.RE
+.RS
+.TP
+.B nordahead
+Turn off file readahead. Usually the OS performs readahead on every read
+request. This usually boosts read performance but can be harmful to
+random access read performance if the system's memory is full and the DB
+is larger than RAM. This option is not implemented on Windows.
+.RE
+
.TP
\fBindex \fR{\fI<attrlist>\fR|\fBdefault\fR} [\fBpres\fR,\fBeq\fR,\fBapprox\fR,\fBsub\fR,\fI<special>\fR]
Specify the indexes to maintain for the given attribute (or
.BR slapadd (8),
.BR slapcat (8),
.BR slapindex (8),
-OpenLDAP MDB documentation.
+OpenLDAP LMDB documentation.
.SH ACKNOWLEDGEMENTS
.so ../Project
Written by Howard Chu.