Re: (ITS#5189) slapadd -q breaks db_stat -c

[h.b.furuseth@usit.uio.no]

hyc@symas.com writes:
> These are backend-specific considerations. Feel free to file an ITS
> against the slapd-bdb(5) manpage if you wish.

Might as well be this one.  "Need to document what you are explaining
here."  Probably mostly in the Admin Guide with a few notes in the
manpage.

> Any operation will acquire a lock for every single DB page it
> touches.  (...)

I don't think that can be quite right.  A search which traverses the
database would need an awful lot of locks.  Unless for the entries
it acquires and then releases the locks for one entry at a time.

> The more work that an operation needs to do, the more pages
> it will touch, the more locks it will need. (...)

Another item would be entries needed to evaluate access controls, I
assume.

>> Sleepycat messages can be scary.  I came from the slapadd "wrong dynamic
>> library" or message or whatever it was which the mailinglist says is
>> cured with more locks & lockers, so I increased those and just got
>> another error message (this ITs).  So apparently, something still wrong.
>
> I'm not familiar with that message or advice.

Just reproduced it.  Out of locks (so of course configure more), then
"Accessing a corrupted shared library".  Will file a separate ITS, it
doesn't sound like slapadd in a clean directory should need 1000+ locks.
http://www.openldap.org/lists/openldap-software/200607/msg00305.html

>> "Not configured for the locking subsystem" sounded like a permanent
>> problem with the database build, not that it would get "reconfigured"
>> to support locking when needed.  Hence this report.  Oh well.
>
> The message said The Environment is not configured for locking. It
> didn't say the BDB library.

Yes, that's what I meant.  The database, with its enviroment, I just
built with slapadd.

> Really there's nothing mystical or spooky here, and if you've actually
> read the BDB documentation you'll know what The Environment refers
> to. If you're using back-[bh]db without having read the BDB
> documentation, despite all the recommendations to do so, you deserve
> to be scared.

I've read it.

-- 
Regards,
Hallvard