From: Linus Torvalds Date: Sat, 10 Sep 2005 19:07:47 GMT Subject: Re: git-bisect failure Message-ID: In-Reply-To: <20050910022638.20832803.akpm@osdl.org> On Sat, 10 Sep 2005, Andrew Morton wrote: > > Junio C Hamano wrote: > > > > So it _might_ > > be possible that you said "current LDT" was bad when it was > > actually good. That is one possible explanation. > > I agree. Mea culpa. Sorry. Well, this was actually something I hit when testign bisection too: it _is_ very unforgiving of mistakes. That _may_ be something fundamental (hey, the point of bisection is that you can get a lot of work done thanks to the log2(n) behaviour, but it also means that a mistake ends up being easily multiplied). But on the other hand, maybe there could be nicer interfaces. In particular, I suspect that we should save off the sequence of good/bad markers, so that it can be more easily re-created. Right now we only track the last "bad" marker, and we don't keep track of the order of the ones marked good. That's technically _sufficient_ for the job, but maybe we should have more of an audit trail. With an audit trail, people could re-do the bisection if something goes wrong. Right now, if you by mistake mark something bad, and you immediately realize that it was a mistake, you can't undo it - because the old bad state was overwritten. So the bisection algorithm may have done the right thing from a technical standpoint, but I suspect it could be made to be a bit more forgiving, or at least when somebody realizes that bisection didn't work right, we could have the trail of good/bad markings to try to debug what happened... Linus