Hi!
On Sun, 2019-03-03 at 02:38:10 +0100, Vincent Lefevre wrote:
> On 2019-03-03 00:15:13 +0100, Guillem Jover wrote:
> > Did this start happening due to the new kernel version?
>
> In March 2018, this was already slow, but much less:
>
> [...]
> 2018-03-08 00:55:55 status unpacked texlive-fonts-extra:all 2017.20180225-1
> 2018-03-08 00:55:55 status half-installed texlive-fonts-extra:all
> 2017.20180225-1
> 2018-03-08 01:02:55 status half-installed texlive-fonts-extra:all
> 2017.20180225-1
> 2018-03-08 01:02:56 status unpacked texlive-fonts-extra:all 2017.20180305-2
> 2018-03-08 01:02:56 status unpacked texlive-fonts-extra:all 2017.20180305-2
> [...]
>
> I don't have older information.
>
> > What filesystem are you using (say btrfs or similar?),
>
> mount information:
>
> /dev/mapper/zira--vg-root on / type ext4 (rw,relatime,errors=remount-ro)
>
> > etc, can you reproduce on another system? I certainly can't. :)
>
> No, on two of my other machines, it takes around 1 minute
> (both for old and new versions). I assume that this is what
> is expected.
Yes. This does really look like a kernel or hardware issue TBH.
Could you try downgrading the kernel to earlier versions to see
whether that improves, that'd give a definitive answer.
I'd say try also older dpkg versions, but I seriously doubt that'd
change much, as I don't remember any major changes in this area
recently.
> > I guess attaching strace to the running dpkg might also give some more
> > info on what's going on, or where it's stalling. Also if you can
> > simply reproduce via «dpkg -i», then enabling all dpkg debug flags
> > might also help.
>
> With
>
> dpkg -i /var/cache/apt/archives/texlive-fonts-extra_2018.20190227-1_all.deb
>
> GKrellM shows full disk activity for a bit less than 2 minutes, then
> no activity, but dpkg is still running. Attaching strace against it
> during this time shows lots of rename's:
>
> [...]
> rename("/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2cijw8y.tfm.dpkg-new",
>
> "/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2cijw8y.tfm")
> = 0
> openat(AT_FDCWD,
> "/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2ciw8y.tfm.dpkg-new",
> O_WRONLY) = 11
> fsync(11) = 0
> close(11) = 0
> rename("/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2ciw8y.tfm.dpkg-new",
>
> "/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2ciw8y.tfm")
> = 0
> openat(AT_FDCWD,
> "/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2cj8c.tfm.dpkg-new",
> O_WRONLY) = 11
> fsync(11) = 0
> close(11) = 0
> rename("/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2cj8c.tfm.dpkg-new",
> "/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2cj8c.tfm")
> = 0
> openat(AT_FDCWD,
> "/usr/share/texlive/texmf-dist/fonts/tfm/arkandis/berenisadf/ybdr2cj8t.tfm.dpkg-new",
> O_WRONLY) = 11
> fsync(11) = 0
> close(11) = 0
> [...]
Thanks. Yes this would be the code doing the delayed fsync(3 ) with
atomic renames(3), which has been the solution to earlier problems
with ext4.
Thanks,
Guillem
