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Re: a few MDB questions

I think I may have answered my own questions. The number of leaf nodes being limited to 1000 was a red herring - an artifact of the default settings of the LDAP browser I was using (slaps forehead).
I compiled OpenLDAP on a 64bit linux system and was able to specify a maxsize greater than 4G so I think that's that. Now I just gotta change my dev/testing environment over to a 64bit system is all. :-)
BTW, thanks to everyone who contributed to MDB. At first glance it's very fast and a big improvement. Can't wait to feed it some decent amounts of data (this first DB I'm testing with was around 95 gigs using BDB) and see how it compares then. Won't be a completely fair comparison since the old DB was on a 32 bit linux, but (shrug)... 

Brent

On 09/02/2013 12:22 PM, Brent Bice wrote:

    I'm trying out the mdb backend before converting several of our LDAP
servers to it and have a few questions I haven't found answers to yet.

    Firstly, I found when I spun up an instance using MDB that I
couldn't have more than 1000 leaf nodes.  It appears when I tried to
create the 1001st leaf node, one of the earlier nodes disappeared.  Is
this a known limitation or just a config option I don't see in the
slapd-mdb man page?  Right now my config just contains:

database    mdb
masxize        2147483648
suffix          "dc=mysuffix,dc=com"
rootdn          "cn=Manager,dc=sgi,dc=com"
rootpw        myrootpw
directory       /data/ldap/instance-v1.4/var/openldap-data
[... a bunch of indexes ...]
checkpoint      1024000 60

    The total size of the DB was only 412 megs so far and each of three
branches in the DB appeared to be limited at 1000 leaf nodes so I don't
think I was just hitting a maxsize limit.

    Which leads me to the 2nd question... The maxsize option (according
to what I've read) is the maximum size of the database in bytes.  But it
looks to me like the biggest value I can specify is 4G - the biggest
value for an unsigned long.  Would this be cuz the system I'm testing on
is a 32bit version of linux?  (unsigned long is only 4 bytes whereas on
a 64 bit OS unsigned longs are 8 bytes)

    I can just switch to a 64 bit system, easy-peasy. But I'm not sure
why I seem to be limited to 1000 leaf nodes.

Brent