On Wed, 2020-06-03 at 09:06 +0300, Panu Matilainen wrote:
On 6/2/20 7:25 PM, Adam Williamson wrote:
> On Tue, 2020-06-02 at 11:05 -0500, Richard Shaw wrote:
> > On Tue, Jun 2, 2020 at 10:25 AM Adam Williamson
<adamwill(a)fedoraproject.org>
> > wrote:
> >
> > > On Tue, 2020-06-02 at 06:34 -0500, Richard Shaw wrote:
> > > > boost-devel, nosync=False, bootstrap=True
> > > > real 1m13.294s
> > > > user 0m6.723s
> > > > sys 0m2.761s
> > > > ---
> > > >
> > > > So it looks like boostrap=True and nosync=False is the culprit, which
I
> > > > inadvertantly got myself into. I did have either set and of course
nosync
> > > > would be False by default and it looks like bootstrap=True by default
for
> > > > rawhide.
> > >
> > > When you say 'bootstrap', which setting do you mean exactly? I
don't
> > > see one that's just called 'bootstrap', I see
--(no-)bootstrap-chroot
> > > and --(no-|use-)bootstrap-image .
> > >
> >
> > $ cat .config/mock.cfg
> > config_opts['cleanup_on_failure'] = False
> > config_opts['nosync'] = True
> > config_opts['use_bootstrap'] = False
> >
> > I got this from the documentation, maybe should have searched a bit more,
> > didn't think there was more than one bootstrap option.
>
> That seems to be the same as --bootstrap-chroot , i.e. --no-bootstrap-
> chroot should set it False.
>
> So, if I explicitly set nosync = True in mock.cfg it goes back to being
> as fast as I remember. But that's somewhat odd, because:
>
> a) I definitely didn't have explicit config to turn nosync on before
> b) I didn't actually have the nosync packages installed at all until
> after I hit this problem
>
> so it seems like somehow before I was getting fast performance without
> using nosync, but now I need it? Weird...
Okay, that's useful. I'm not at all familiar with how this all actually
works in mock but I see that nosync.so is being copied around etc, and
with bootstrap introducing an extra layer in between, it's not hard to
imagine a subtle bug or two in there. Just a guess though.
The thing is, I'm really pretty sure I *wasn't using* mock's nosync
support before. I don't see how I could have been, since I didn't have
nosync installed. So this still seems kinda mysterious. Either somehow
it wasn't fsync'ing before but it is now, or somehow disk writing
performance on my system fell off a cliff?
I'll try and poke it some more tomorrow if I can, try some old kernels
and/or old mock builds or something.
--
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Twitter: AdamW_Fedora | XMPP: adamw AT happyassassin . net
http://www.happyassassin.net