I'm sorry it took me so long to get back to you! I get what you're saying and it
seems like a possible explanation for some scenarios.
However, I'm still not sure it applies to my case, where 389 DS behaves completely
normal for a few minutes and then an instantaneous jump to full CPU usage occurs.
I created three pstack traces:
was taken while the load test was already running and 389
DS still behaved normally.
is one minute later. The same load test is still running,
but now 389 DS uses all CPUs and is very slow.
is after stopping the load test, 389 DS is now idle.
It would be great if you could take a look at those traces!