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Re: indices in slapd.conf

 "Mike Denka" WROTE:

> I am selectively replicating data from my master ldap server to the
> slaves.  So the data the slaves receive from the master is only partial.
> Because of this and because the master has some front end software that
> allows us to manipulate the data via a web interface, I access data from
> ldap in different ways on the master and slaves.  My question is
> twofold:
> 1) Can I use different indices on the slave servers than on the master?
 yes , you can. in my system (i have one master and two slaves) i used
different index
because the master is for write operations mainly, operations via web. And
my slaves
are used to router the mail.

> 2) And what are the considerations when deciding which and how many
> indices to use in slapd.conf?  Obviously you want to use the attributes
> you search for most often as indices, but what is the penalty for using
> more indices rather than less?  What is the order of magnitude of memory
> usage and other penalties related to the number of indices you use?
> Does memory double as indices double, for example?  Or is it a fourfold
> increase in memory when the number of indices doubles?  What are the
> pitfalls and caveats one should observe when customizing indices?

the exact penalty for use index depends of the type of db that you use.
but the problem with a lot of indexes not is at the search. the problem is
at updates
because one lonely update require that a lot of files are updates too.

> Thanks,
> Mike