Re: slapd problems under stress

[Mark Valence <kurash@sassafras.com>]

Stephen-

> I can send you the test program (I don't think it is interesting enough
> to send it to the list...)

Can you send me a tarball with source and a Makefile?

>  > >I think that the problems are thread related.
>  > >Are there any known problems? Is it possible to set a limit
>  > >on the number of concurrent threads?
>  >
>  > You can change line 97 in servers/slapd/init.c to something like:
>  >
>  >    ldap_pvt_thread_pool_init(&connection_pool, 5, 0);
>  >
>  > where the second parameter is the maximum number of concurrent threads.
>
> That seems to improve things a lot! I couldn't crash the system with the
> ldbm-backend anymore if I apply that patch. I even get answers to all
> the requests :-). I'll try our backends on monday.

Sounds to me like a deadlock problem, where the worker threads are 
not completing, and so you get more and more threads (960!) on your 
system until you crash.  Can you experiment with values of 
max_concurrency (the second param above)?  Interesting values would 
be 1, 10, 100, 500, and 1000.  Which values are OK, and which aren't?

> Shouldn't the maximum number of concurrent be a configurable parameter?

This might already be started.  Anyway, I'll look into it.

Mark.