Hi,
Another timeout use: in case of an application deadlock (not our fault),
tx timeout seems to be the only "clean" way out.
Sebastien
marc fleury wrote:
>
> So I see 2 usages of time out...
>
> one is a "time-out" because someone went to lunch and we don't want to tie
> up resources on the server, passivation won't do since we are in a
> transaction.
>
> the other one we see under test, is that under very heavy load (we are
> doing the tests right now), like loads that puts a good lunix machine under
> x5 CPU load, the server time-outs the transactions after awhile.
>
> BTW sebastien found a fix for that "timeout bug" that I described before and
> it now works, the server doesn't lock at all. it runs *very* well.
>
> So now under very heavy load it throws many exceptions (timeout exceptions)
> but it goes on very happily.
>
> My question is this
> 1- can't we put a time out at 1hour or so. The reason is very simple. I
> was always impressed by the "stability" of linux... ie. under very heavy
> load, it swaps and goes slow and what not but it carries on and finishes.
> If we put one hour, under the loads described (hey even the big SAP install
> I know of don't go up to 1000 concurent clients all on the SAME instance),
> then the server will surely take the time to answer (it will be slow) but at
> least IT WON"T THROW EXCEPTIONS on timeouts.
> 2- Ole, we have tried to change the time out time on your timeout factories,
> but with no success whatsoever... how do you do it?????
> 3- In case we go with 1, then the "load" should be done in a
> "MetricsInterceptor" that can provide some feedback on the time it takes to
> complete a call, the number of beans in the container, the number of threads
> that are in etc etc... we can then provide an MBean that gives all that
> information. (time in-time out etc etc)... hey the famous group 77 s'got to
> be good for something...
>
> open to opinions...
>
> stability? metrics? exceptions?
>
> my vote is clear: percieved stability is very important... and the fact is
> that the container is super-stable even under very heavy load... so why give
> a bad impression on timeout exceptions, people will see that it is slow and
> that is all the information they need, or eventually a "mail" from the new
> interceptor that says "buy some more hardware dude!" but not these nasty
> "timeout exceptions".... I don't know, what do you think?
>
> regards
>
> ________________
> Marc Fleury, PhD
> CTO, Telkel Inc.
> ________________
