[Bug 1181720] Re: grub with partition detection issues (horribly slow) since recent update in 13.04

[Lars Steinke]

Hi Phillip,

1. my reference to extlinux was simply because a new directory /boot/extlinux popped up that wasn't there in 12.04.
2. update-grub has always created one grub boot menu entry for my md0 root partition and then two additional entries for sda1 & sdb1 (the two md0 RAID1 members) - so, in a way, raid does affect the menu ;)...

Please find the requested bootinfoscript output attached, it is a
somewhat convoluted dual boot setup with Ubuntu spread across a raid1
and lvm on raid1...

I have been able to narrow down the problem to os-prober (so you might have to reassign the bug to that package):
Setting "GRUB_DISABLE_OS_PROBER=true" in /etc/default/grub solves the problem, as long as I add a manual entry for my Win7 dual boot in /etc/grub.d/40_custom:

menuentry "Microsoft Windows 7 Professional (on /dev/sdc1)" --class windows --class os {
        insmod part_msdos
        insmod ntfs
        set root='(hd2,msdos1)'
        search --no-floppy --fs-uuid --set=root 086431136431054A
        drivemap -s (hd0) ${root}
        chainloader +1
}

I have a hunch that my introduction of a SSD into the former two HDD
raid setup might confuse os-prober somewhat: During the grub os-probe in
12.04 there have been complaints about "invalid LVM signatures"
(possibly from sdc as I expelled that drive from the raid set with LVN
on top) that have disappeared with 13.04...

Thanks!

** Attachment added: "gzipped bootinfoscript output"
   https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1181720/+attachment/3682249/+files/boot.inf.gz

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to grub2 in Ubuntu.
https://bugs.launchpad.net/bugs/1181720

Title:
  grub with partition detection issues (horribly slow) since recent
  update in 13.04

Status in “grub2” package in Ubuntu:
  Incomplete

Bug description:
  1. grub-update takes ages scanning for boot menu entries in the 30_os-prober step (about 35% system load ), which makes kernel updates or removals really painful:
  real	7m54.745s
  user 0m49.140s
  sys	1m8.912s
  2. upon booting, the grub boot menu only appears after several minutes of a monochrome violet screen

  Ubuntu 13.04 is booting from a md RAID1 array (which accounts for two
  grub menu entries) and there is one additional Windows boot entry per
  disk.

  These issues appeared with a round of updates on 13.04 (now 2.00-13ubuntu3), about two weeks ago:
  After the initial update from 12.10 to 13.04 they were not apparent right away (even though it seems 13.04 has introduced extlinux as a chainloader for grub?)...

  ProblemType: Bug
  DistroRelease: Ubuntu 13.04
  Package: grub2-common 2.00-13ubuntu3
  ProcVersionSignature: Ubuntu 3.8.0-21.32-generic 3.8.8
  Uname: Linux 3.8.0-21-generic x86_64
  NonfreeKernelModules: fglrx
  ApportVersion: 2.9.2-0ubuntu8
  Architecture: amd64
  Date: Sun May 19 12:52:58 2013
  MarkForUpload: True
  ProcEnviron:
   TERM=xterm
   PATH=(custom, no user)
   XDG_RUNTIME_DIR=<set>
   LANG=de_DE.UTF-8
   SHELL=/bin/bash
  SourcePackage: grub2
  UpgradeStatus: Upgraded to raring on 2013-04-29 (20 days ago)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1181720/+subscriptions