compcache locks the system; Was: Swap problems

[email.listen at googlemail.com]

On Tue, 10. February 2009 12:58:05 Oliver Grawert wrote:
> hi,
>
> On Mo, 2009-02-09 at 21:03 +0100, email.listen at googlemail.com wrote:
> > > better edit /etc/initramfs-tools/initramfs.conf, make sure there is no
> > > value set for compcache and run sudo update-initramfs -u
> > > that will prevent compcache from being used at all ...
> >
> > Really???
> > I don't think so.
> > At least here compcache is used even without a size entry in
> > initramfs.conf. I also did an 'update-initramfs -u' without result so
> > far...
> >
> > > you should also file a bug about the lockup so it can be fixed ...
> >
> > "https://bugs.launchpad.net/ubuntu/+source/linux/+bug/318100"
> > I would think it's a known bug, isn't it?
> > To be honnest, I'm a bit puzzled here.
>
> well, i can just say me too, i wrote the scripts that are dynamically
> putting the compcache stuff into initramfs and without having
> COMPCACHE_SIZE set they are a complete no-op.
> compcache should never be used on any installed system unless explicitly
> told so by setting the value in initramfs.conf or through a file in one
> of the two conf.d dirs ...
>
> can you check if you have anything lying around
> in /usr/share/initramfs-tools/conf.d/ 

BINGO!

find /usr/share/initramfs-tools/conf.d/ -type f -exec grep -iH compcache {} \;
  /usr/share/initramfs-tools/conf.d/compcache:COMPCACHE_SIZE="25%"

Ctime of file compcache is 2009-01-13

Problem is solved after deleting /usr/share/initramfs-tools/conf.d/compcache 
and a: 

  sudo update-initramfs -u 


> or /etc/initramfs-tools/conf.d/ that could set COMPCACHE_SIZE ?
>
> while that update bug above is nice to know about, the fact that
> compcache is loaded at all for you is definately a different bug.file

So, my deepest condolence to those who need compcache activated. 
It is unstable and totally locks the system.
If this will happen to a novice user who want's to have a preview on ubuntu 
during with live cd session...

I would drop the distribution like a 'hot Potato' as we like to say in DE_de.

I can't imagine a better showstopper than this.

> in ubuntu there are only two occasions where compcache should be used by
> default, one is on thin clients that have a low ram footprint and the
> other is on the livecd during the livesession if your system has less
> than 512M RAM.
> a standard install shouldnt have compcache enabled at all, if thats the
> case for you this is a new bug to be filed and fixed before release...

I would say there are two bugs.

1. the instability of compcache itself, locking the system
2. the problem of an mistakenly activated compcache 


regards,
thomas