From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Wed, 21 Jan 2009 00:10:22 GMT
Subject: Re: valgrind patches, was Re: What's cooking in git.git (Jan 2009, #04; Mon, 19)
Message-ID: <alpine.DEB.1.00.0901210105470.19014@racer>
In-Reply-To: <20090120232439.GA17746@coredump.intra.peff.net>

Hi,

On Tue, 20 Jan 2009, Jeff King wrote:

> On Tue, Jan 20, 2009 at 03:50:28PM +0100, Johannes Schindelin wrote:
> 
> > > How will you deal with race conditions between two simultaneously 
> > > running scripts? I.e., where are you going to put it?
> > 
> > There are no race conditions, as for every git executable, a symbolic 
> > link is created, pointing to the valgrind.sh script [*1*].
> 
> Hmm. I suppose that would work, since every test run is trying to create 
> the same state.

Yep, that's what I meant with "no race".

> > Besides, what with valgrind being a memory hog, you'd be nuts to call 
> > valgrinded scripts simultaneously.
> 
> I have to disagree there. I think there are two obvious usage patterns:
> 
>   - run script $X specifically under valgrind to track down a bug
> 
>   - run the whole test suite under valgrind occasionally to find
>     latent bugs that wouldn't otherwise show up
> 
> In the latter, you want a pretty beefy box.  When I did the original
> patches, I ran through the whole test suite under valgrind. It took
> several hours on a 6GB quad-core box, using "-j4". I would hate for it
> to have taken an entire day. :)

Heh.  Okay.  I was convinced that your valgrind patch predated my -j<n> 
patch...

In any case, I already found a bug in the nth_last series, thanks to your 
work, which I'll send in a minute.

Ciao,
Dscho