Hi, I'm Axel Naumann from Cern.
Cern is a physics Laboratory.
It's one which does basic physics research.
We are just curious over here.
We are trying to understand nature even better
than we do already and we do that by means
of a particle accelerator.
Now the problem that people face over here,
and with people I mean those building the
detector, people who write the software and
the physicist doing the analysis.
The problem that they face over here is precision.
The way that we improve precision by having
lots of data because if things happen more
often, then we can be more certain that they
actually did happen and that is why we have
these four terabytes of data that we take
every year, just to be sure we see the rare
things often enough.
Now of course, software and analysis and also
the detector have inefficiencies so that we
miss some of the spectacular things we are
looking for.
By improving the software, we can thus accelerate
the results.
We have means to measure the quality of the
software, but of course we don't want our
software to not be sensitive to a certain
particle.
Say there comes a HIGGS, if our software would
crash every time there was a HIGGS in the
data, then we would never find it.
So, even though we can measure the quality,
we still want to make sure that it is as bug
free as possible.
At CERN, we have a software base of approximately
50 million lines of code.
That is mostly experiment software.
One part that is shared by all the experiments
because it is a tool to them is the root project
software.
That's about 2.5 million lines of code.
We ran Coverity originally only on the root
project as a test case basically because even
2.5 million lines of code that is a lot of
lines of code.
When we were seeing the results and the quality
and the relevance of the reports, we then
went over to the experiments and offered it
to them.
Now, despite of all of the comply list we
use, which really did a great job in finding
problems with our code, there were a few cases,
very interesting ones also, that really only
Coverity finally discovered.
Unbelievable that we with all of our machinery
did not manage to find it before.
So we looked at a few tools and some of them
even had websites for their reports of the
static analysis.
The nice thing about Coverity is that the
reports it has are very easy to understand.
Of course, that also helps in adoption because
if you have relevant reports and that are
easy to understand then you can convince people
to go fix the code.
So, for us Coverity really improved the quality
of our software, both for the tools, like
root, and for the experiment software.
I really hope that we finally manage to find
the HIGGS, maybe this year, maybe next year
and I hope of course that we get a high quality
precise measurement here at CERN.
And I would say, once we find it, if we find
it, that Coverity has its share in that result.
