Re: mdb index reporting available?

[Quanah Gibson-Mount <quanah@symas.com>]

--On Saturday, August 17, 2019 1:29 PM +0200 Marc Roos 
<M.Roos@f1-outsourcing.eu> wrote:

> I used to have some help with what and how I should add indexes, but it
> looks like the new mdb backend is not telling me anymore. Is this
> correct? Anyway to get a warning when some index needs to be set?

back-mdb logs whether or not indices are set the same way as back-bdb and 
back-hdb, at any log level.  You can trivially see this in the code:

   if ( rc == LDAP_INAPPROPRIATE_MATCHING ) {
       Debug( LDAP_DEBUG_ANY,
           "<= mdb_equality_candidates: (%s) not indexed\n",
           ava->aa_desc->ad_cname.bv_val, 0, 0 );
       return 0;
   }

Note the "LDAP_DEBUG_ANY".  It is always important to understand that there 
are situations in which indexing can negatively impact performance rather 
than improve it.  Thus why it is important to know what searches are being 
performed that are generating those messages.  This information can be 
obtained by using the "stats" log level.  Generally you will also find that 
without the "stats" level of information, diagnosing problems that occur 
will be next to impossible, regardless of backend.  If replication is 
involved, "stats sync" logging will generally be required, again regardless 
of what backend is in use.

Furthermore, regardless of backend used, I'd advise using a more current 
release than 2.4.44 which was released 3.5 years ago.  The current release 
is 2.4.48 from July 2019.  You should likely read the change log for 
OpenLDAP found at <https://www.openldap.org/software/release/changes.html>. 
You generally have 3 options in this:

a) You can use the builds from the LTB project found at 
<https://ltb-project.org/documentation/openldap-rpm#yum_repository>.  These 
install into /usr/local, so are isolated from the system libraries, etc. 
Fixes released after 2.4.48 will not be included in these builds.

b) You can use the drop-in replacement builds from Symas: 
<https://repo.symas.com/sofl/rhel7/>.  Any critical fixes post 2.4.48 will 
be added to these builds.

c) You can build and maintain your own OpenLDAP packages.

Regards,
Quanah


--

Quanah Gibson-Mount
Product Architect
Symas Corporation
Packaged, certified, and supported LDAP solutions powered by OpenLDAP:
<http://www.symas.com>