Bug#850233: mavibot: FTBFS randomly (sbuild hangs)

[Santiago Vila]

On Fri, Jan 06, 2017 at 12:22:36PM +0100, Emmanuel Bourg wrote:
> Le 5/01/2017 à 11:05, Santiago Vila a écrit :
> > Running org.apache.directory.mavibot.btree.MultiThreadedBtreeTest
> >  Time to create 1M entries : 4 seconds
> > Written 0 elements
> > Written 100000 elements
> > Written 200000 elements
> > Written 300000 elements
> > Exception: java.lang.OutOfMemoryError thrown from the UncaughtExceptionHandler in thread "Thread-102"
> 
> 
> > I don't know how to reproduce this, sorry, but it happened at least twice to me.
> 
> Hi Santiago,
> 
> The tests ran out of memory. How much memory was assigned to the builder?

Ooops! They were actually the smallest size I use: 768 MB of RAM plus 1 GB of swap.
(I'm closing this bug with this message).

I have a list of regexps to check for things like this.
So I'll add another one for java.lang.OutOfMemoryError.


But I still don't understand why it should fail. I measure the
allocated memory by looking at Committed_AS in /proc/meminfo, and this
package has never required more than 900 MB (less than 768MB + 1GB).

Maybe it's the stack (not the heap, measured by Committed_AS) what
my autobuilders had not enough?

How could I ensure that this does not happen again in the general case?

(Sorry if this is a stupid question, I don't know a lot about this
low-level things).


There is also another problem: I have at least one *successful* build
containing an error like that (see attach).

Is this not a violation of Policy 4.6? (That's the rule saying that
whenever there is an error, the build should stop).

Thanks a lot.