Re: file backend

[Jonghyuk Choi <jongchoi@us.ibm.com>]

>Not sure if you mean search indexes or not having the entire database in
>memory, but anyway I don't think so.

Actually both: the entries for a given "search index" are represented by their
IDs by which entries are identified in the database as well as in the entry cache.

>And without search indexes, a search must inspect every entry in the
>database to find out if it matches - so if the database is not in
>memory, it must in effect be rebuilt for every search.

>With each entry in memory, this backend will perform like a bdb/ldbm
>backend with unlimited cache but no indexes.  So it should not be
>used for very large files anyway.

For small directories, yes.

For large directories, managing entry locations in the file
can improve search performance in a memory constrained case
and can open the possibility of indexing support.

------------------------
Jong Hyuk Choi
IBM Thomas J. Watson Research Center - Enterprise Linux Group
P. O. Box 218, Yorktown Heights, NY 10598
email: jongchoi@us.ibm.com
(phone) 914-945-3979    (fax) 914-945-4425   TL: 862-3979