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Re: [ldap] Implementation Suggestions

I'm no expert, but I do run on Solaris (9), a couple of things I can
think of...

It may be worth adding the noatime flag to the filesystems that hold
data and (bdb) logs. You are indexing a lot of attributes, do you need

No atime? That's interesting. I've never heard of that, what does that do? As for the BDB logs, is it a reasonable thing to think "this is totally read only and if i lose the data, I regenerate it . . . that means I don't really need BDB's transaction logs"? I didn't see how to turn them off exactly, but I don't know that I need them given that I'd sooner regen everything than I would attempt to get BDB to roll back.

that many (are they based on what queries you are actually getting or
those you expect you might get?) - indexes speed up searches but slow
down writes so if you're experiencing performance problems during writes
it can be worth checking if you really need all the indexes. Do you
need the same indexes on all slaves, do they all see similar traffic?

There are not based off actual indexes, they are based more off of everything folk have suggested they would search on. I noticed that if I don't have an index at all, that searches appear to flat out not work. So I seem to have to have -something- if I want folk to be able to search on that field. Is this not true? Was something else causing that hooha? My primary goal here was to provide "as searchable as possible" of a database, and try to govern as little as possible how people want to use it.

You have enough memory for 1.25 Gb of bdb cache? You don't post your

I should hope so, they have 2.5 Gb of ram each. Sorry about the lack of posting, I posted that info on ldap@umich.edu and forgot to do it here as well. What we have is a pool of 4 SunFire V210s. 2.5Gb ram each. Separate drive for the bdb data directory from everything else. 3 of these are replicas/slaves. 1 on of them is a master. We operate in a readonly environment as we are not the authoritative source on any of this information. No users can directly update information in LDAP, all handled through scripts on the master that push out changes via slurpd. The entire pool is load balanced via Ldirector (linux-ha.org) and, for example, if one croaks and I needed to regenerate the database, I would just take it out of the pool and repopulate it instead of trying to repair the tattered remains of BDB. =D

machine spec so its difficult to say if that is sane, but make sure its
not using lots of swap. I note that your bdb logs are on the same disk
as your swap (and your syslogs presumably), so if you are swapping (or
anything is logging heavily) that will have an impact on bdb writes.

Given I only currently have 2 disks, is this an important "you need to add another disk" or ... ? I read some articles about how I needed to have the data separate in the past but that the logs would be ok. Also note again that I'm still not sure I need those logs.

Thanks for your response!!



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