ureahead-other main process terminated with status 4

[joneall]

I know there is a bug report for this at https://bugs.launchpad.net/ubuntu/+s...ad/+bug/484677, but that seems to be mainly a sometimes-heated discussion between a developer and some others about just what the bug is.

What I know is that, frequently but not always (say once out of 5 or 10 boots), my computer hangs in boot just after this message is displayed on the screen.

I'm in Lucid 10.04, vmlinuz-2.6.32-24-generic-pae (whatever that may mean), 32bit.

My filesystems are as follows

$ df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sdb1 16253880 5137292 10290940 34% /
none 2052768 368 2052400 1% /dev
none 2056972 0 2056972 0% /dev/shm
none 2056972 120 2056852 1% /var/run
none 2056972 0 2056972 0% /var/lock
none 2056972 0 2056972 0% /lib/init/rw
/dev/sda3 157286396 69409424 87876972 45% /mnt/win_d
/dev/sdb5 7874528 150560 7323952 3% /tmp
/dev/sdb6 125988604 56681984 62906728 48% /home
/dev/sdb7 132109124 85677036 39721340 69% /home/jon/music_mp3
/dev/sda2 52326396 20683420 31642976 40% /mnt/win_c
/dev/sda7 72246408 28059876 40516488 41% /home/jon/travel_pix

so there is no separate /var.

Side question: What are all those things like "none 2052768 368 2052400 1% /dev"?

[GreyGeek]

Re: ureahead-other main process terminated with status 4

Regarding the bug report, msgs #40 and #65 say it all. Scott is 100% correct. That several vociferous "reporters" disagree is irrelevant. Facts overrule "group think", because what the group "thinks" is wrong. Several were reporting their boot errors as ureadahead problems because they saw the "exit with status 4" and assumed that the exit was an error. It was not. Upstart was merely blindly passing on the ureadahead exit msg when it should have gone only to the logs. Some had boot errors because they manually included mounting instructions for Windows partitions in fstab and those instructions included volume names which had spaces ... a no-no.

As far as your question about the output of "df" - - perhaps another set of df switches will clarify things for you:

jerry@sonyvgnfw140e:~$ df -aT
Filesystem Type 1K-blocks Used Available Use% Mounted on
/dev/sda1 ext4 237481656 55181300 170236972 25% /
proc proc 0 0 0 - /proc
none sysfs 0 0 0 - /sys
none fusectl 0 0 0 - /sys/fs/fuse/connections
none debugfs 0 0 0 - /sys/kernel/debug
none securityfs 0 0 0 - /sys/kernel/security
none devtmpfs 1474128 332 1473796 1% /dev
none devpts 0 0 0 - /dev/pts
none tmpfs 1478640 0 1478640 0% /dev/shm
none tmpfs 1478640 100 1478540 1% /var/run
none tmpfs 1478640 0 1478640 0% /var/lock
none tmpfs 1478640 0 1478640 0% /lib/init/rw

and this listing of MOUNTED file systems should help, too:

jerry@sonyvgnfw140e:~$ cat /etc/mtab
/dev/sda1 / ext4 rw,errors=remount-ro 0 0
proc /proc proc rw,noexec,nosuid,nodev 0 0
none /sys sysfs rw,noexec,nosuid,nodev 0 0
none /sys/fs/fuse/connections fusectl rw 0 0
none /sys/kernel/debug debugfs rw 0 0
none /sys/kernel/security securityfs rw 0 0
none /dev devtmpfs rw,mode=0755 0 0
none /dev/pts devpts rw,noexec,nosuid,gid=5,mode=0620 0 0
none /dev/shm tmpfs rw,nosuid,nodev 0 0
none /var/run tmpfs rw,nosuid,mode=0755 0 0
none /var/lock tmpfs rw,noexec,nosuid,nodev 0 0
none /lib/init/rw tmpfs rw,nosuid,mode=0755 0 0
jerry@sonyvgnfw140e:~$

You may want to read this.

FileSystems (1st column) with physical names have physical attachments. Others are temporary or memory resident.

Tmpfs is

a common name for a temporary file storage facility on many Unix-like operating systems. It is intended to appear as a mounted file system, but stored in volatile memory instead of a persistent storage device. A similar construction is a RAM disk, which appears as a virtual disk drive and hosts a disk file system.

For more info on tempfs and ramfs read this.

Devpts are from /dev/pts, a pts is short for a character device called "pseudo terminal slave", which is where we get our command line capabilities from.

The "devtmpfs" program is a kernel component that is used to create the device filesystem when the system boots.

Sysfs is a virtual file system provided by Linux 2.6 which exports information about devices and drivers from the kernel device model to userspace.

Debugfs is explained here.

And, securityfs is explained here.

[joneall]

Re: ureahead-other main process terminated with status 4

I had indeed understood that the bug report had degenerated into a general complaint session. I also understood Scott's evident frustration.

I still don't see why or if my ureadahead message has anything to do with the boot hang.

Thanks for all the pointers about df and file systems. I will read them.

[GreyGeek]

Re: ureahead-other main process terminated with status 4

You are using the pae kernel because you have more than 3GB of RAM on a 32bit machine and you want to use ALL of your RAM.

Your hang is not related to the ureadahead status msg. I can understand why, not being a developer, you don't understand that.

If your splash screen is getting in the way to prevent you from seeing the last msg which appears before the hang you can edit the grub line you boot from and remove the "splash" option so the splash screen won't show and you can see all the boot msgs as they go flying by.

[Telengard]

Re: ureahead-other main process terminated with status 4

Sorry to reopen such an old topic, but I just had some experience with this and found a complete explanation.

I had just upgraded my 9.04 Jaunty system to 9.10 Karmic, and upon reboot was met with a black console login screen. The GUI login screen did not appear, suggesting X had failed to start. On TTY8 I found the ominous looking error message:

"init: ureadahead-other main process (893) terminated with status 4"

Turns out this has nothing at all to do with X, KDM or anything else. it is a separate unrelated problem, which doesn't amount to anything whatsoever. I found a complete explanation of ureadahead here:
http://ubuntuforums.org/showthread.php?t=1434502

As for my X problem, I simply renamed /etc/xorg.conf to xorg.conf.old and rebooted. Xorg is so smart nowadays.

I also learned that Linux filesystems do fragment. The Ubuntu team is working on some kind of dynamic defragger as yet unnamed. Go figure