[Fedora-directory-users] DB object limit question

[David Boreham]

John Call wrote:

>
> Is there a known limit of objects / db?  

A few billion.

> I've recently encountered strange behaviour in my FDS.  The strange 
> behaviour exhibits itself by not allowing searchs within ou 
> containers.  Although if I bind as "Directory Manager" I can search, 
> but it takes a painfully long time for the results to come... on 
> average about 10 minutes.
>
This sounds like an unindexed search is being done (you can tell from 
looking in the access log).
Directory manager is not subject to the lookthrough limit, so ploughs on 
through the entries.
Other users are subject to the lookthrough limit and the search ends 
quickly without
results when the limit is hit (your client _should_ tell you that the LT 
limit was seen though).

> Let me elaborate a little bit about my setup.  I have three ou 
> containers.  The largest container has 253603 entries, the other two 
> containers have 9625, and 4846 objects.  All three of these containers 
> use the same userRoot db.  Through some random tinkering I created 
> another FDS, but instead of userRoot I gave each ou its own db.  The 
> results of each ou having its own db have been positive.  I'm able to 
> search and all expected funcionality is available.

You've probably been able to fox the query planner such that it uses the 
'wrong'
index first. Sometimes you can re-order your filter to achieve the 
result you want
(use the most useful index first). The DS doesn't have the fancy 
statistically driven
index choice query planners that you might see in a high end RDBMS for 
example.