Re: don't bother to use NetBSD Git repos for anything but testing (was: cvs better than git?)
On Thu, 18 Jun 2020 at 15:24, Greg A. Woods wrote: > At Thu, 18 Jun 2020 13:00:50 -0400, Andrew Cagney > wrote: > Subject: Re: cvs better than git? > > > > On Wed, 17 Jun 2020 at 23:23, Mayuresh wrote: > > > > > > On Wed, Jun 17, 2020 at 03:42:44PM +0530, Mayuresh wrote: > > > > For pkgsrc I prefer the git mirror, as I don't have to push anything > > > > anyway and a few hours of latency doesn't matter to me. > > > > > > Don't know whether it's relevant to say on this thread. May be it is. > > > > > > When I use pkgsrc git mirror, after every few days I get this error > when I > > > pull: "fatal: refusing to merge unrelated histories" > > > > It isn't you. > > > > This is a problem with the script that converts the repo from CVS (be it > HG > > or GIT). For some reason, from time to time, commit history gets a > > complete rewrite. > > It is probably not the fault of the conversion process, nor CVS per se. > > It's probably someone, i.e. some NetBSD developer with sufficient > privileges, messing around directly in the CVS repository and doing > things that are contrary to even CVS best practices, let alone what's > good for a repo that undergoes regular conversion. Such conversion > processes typically require absolutely frozen and stable history, and > often even innocuous-seeming changes can cause a ripple in the middle of > the history that must then cause all the changeset hashes to be > recomputed. Only sometimes, and only with extreme care, can such > conversion processes be used securely for any kind of continuous > migration. I've witnessed this regularly with the little tiny SCCS to > Git conversion tool I've been maintaining. > Right. Here though we're talking about the very very first commit which takes the repo from empty to containing the bsd-lite sources. That shouldn't be changing. However if there's something not tied down (such as file order, dates, bonus files, ...) then yes that hash will change. Is the script available? > There's really no point to actually trying to use the Git repos for > anything except infrequent testing, and possibly no point to using the > Hg repos either, until the conversion is 100% frozen with no possibility > of any new change ever being introduced to the original CVS repo again. > > -- > Greg A. Woods > > Kelowna, BC +1 250 762-7675 RoboHack > Planix, Inc. Avoncote Farms >
don't bother to use NetBSD Git repos for anything but testing (was: cvs better than git?)
> There's really no point to actually trying to use the Git repos for > anything except infrequent testing, and possibly no point to using the > Hg repos either, until the conversion is 100% frozen with no possibility > of any new change ever being introduced to the original CVS repo again. Greg A. Woods Is there any timeline on when the conversion to Hg will be finished, and when cvs will no longer be usable for tracking NetBSD source tree? Will pkgsrc also be converted to Hg? I suppose pkgsrc-wip will stay on git? With users reporting extreme slowness with the Hg repos, I don't want to try that now, at least until that problem is fixed. Tom
don't bother to use NetBSD Git repos for anything but testing (was: cvs better than git?)
At Thu, 18 Jun 2020 13:00:50 -0400, Andrew Cagney wrote: Subject: Re: cvs better than git? > > On Wed, 17 Jun 2020 at 23:23, Mayuresh wrote: > > > > On Wed, Jun 17, 2020 at 03:42:44PM +0530, Mayuresh wrote: > > > For pkgsrc I prefer the git mirror, as I don't have to push anything > > > anyway and a few hours of latency doesn't matter to me. > > > > Don't know whether it's relevant to say on this thread. May be it is. > > > > When I use pkgsrc git mirror, after every few days I get this error when I > > pull: "fatal: refusing to merge unrelated histories" > > It isn't you. > > This is a problem with the script that converts the repo from CVS (be it HG > or GIT). For some reason, from time to time, commit history gets a > complete rewrite. It is probably not the fault of the conversion process, nor CVS per se. It's probably someone, i.e. some NetBSD developer with sufficient privileges, messing around directly in the CVS repository and doing things that are contrary to even CVS best practices, let alone what's good for a repo that undergoes regular conversion. Such conversion processes typically require absolutely frozen and stable history, and often even innocuous-seeming changes can cause a ripple in the middle of the history that must then cause all the changeset hashes to be recomputed. Only sometimes, and only with extreme care, can such conversion processes be used securely for any kind of continuous migration. I've witnessed this regularly with the little tiny SCCS to Git conversion tool I've been maintaining. There's really no point to actually trying to use the Git repos for anything except infrequent testing, and possibly no point to using the Hg repos either, until the conversion is 100% frozen with no possibility of any new change ever being introduced to the original CVS repo again. -- Greg A. Woods Kelowna, BC +1 250 762-7675 RoboHack Planix, Inc. Avoncote Farms pgpd3iGSGiuNF.pgp Description: OpenPGP Digital Signature
