Warning: downgrading from Mageia 3 sends akonadi berserk

[mla]

Because of shorewall issues, I briefly reverted to Mageia2. There is always a degree of risk involved in such a downgrade, if both versions share the same /home partition -- desktop configuration files generated by the later version may cause trouble in the earlier one. In this case the result was spectacular. Though I have all of nepomuk firmly disabled, an akonadi-agent process went berserk, hogging all CPU and gradually gobbling all memory. After about 5 minutes the machine became unusable and had to be crashed. Killing the damn thing just delayed the problem, since anoher instance got spawned immediately.

In the end I solved the problem in a crude fashion: replacing /usr/bin/aconadi-agent-launcher with a shell script consisting of a single line: "exit 0".

[wintpe]

you would not have had this issue if you had used clonezilla to backup before upgrade.

regards peter

[mla]

True. But it assumes (a) that I have enough spare disk to clone the home partition, (b) that it would have taken less time to do so than to deal with the problem and (c) that it is undesirable to become aware of such problems, which sometime are but symptoms of deeper trouble. YMMV, but in my book that's three dodgy assumptions.

[penguinclaw]

Wouldn't deleting all the relevant configuration files in your home partition, using a live cd, have solved this issue. It's a practise I always follow, perhaps just keeping mozzila as that is a real pain to set up again.

[mla]

Why bother with live CD? Root console login can do that. And yes, it probably would have done. But you too are making some unwarranted assumptions. (a) The machine in question is used also by the rest of the family, who do not like their config files zapped. OK, I should have spotted the problem on my test rig, on which I first satisfied myself that Mageia 3 would do nicely. But there was no reason to expect that sort of trouble and so I didn't. (b) What configuration files, specifically? I recently had an issue with thunderbird's icon. It displayed just fine as an inactive launcher. It bounced about on the desktop while being invoked.... and then it got replaced by a clank slot on the panel once the prog was running. Only happened on one machine and only on that account. So I zapped .kde4, and the problem remained. So I zapped .local -- still no effect. I never discovered where the problem was. Just cursed, moved the whole home dir out of the way, created a new one, and moved stuff I knew I wanted back into it. Problem's gone away. Now *which* config file was causing it?

[wintpe]

point im makeing is you cant be sure what kind of problems you will expirience after an upgrade.

and how long it will take you to unwind this.

in this case , it may in hindsite be quicker to resolve.

but clonezilla gives you a 100% way to get back.

and a 1 TB drive to backup to is so damm cheap compared with your time.

regards peter

[mla]

I don't need to clone disks to get back. I am runnig rsnapshot which gives me 24 hourly snapshots, 7 daily ones and 4 weekly ones -- all of it fitting nito mere 150% f the size of /home. So yes, I could have blown ecerything back to where it was prior to the upgrade. But as already pointed uot, this is a busy machine used by the rest of the family too. Have yuo ever sorted out differences between not quite identical file hierarchies to make sure other users don't bite your head of? Sure, standard tools help, but its still a tedious and error-prone chore.

Look, just in case there is some misunderstanding... I don't like rubbing it in, but I have decades of experience of running complex Unix and Linux installations, so please don't assume any technical naivity here. OK?

[wintpe]

I was simply trying to shout from the rooftops to everyone, use clonezilla as you can pretty much guarrentee
a 100% fallback when things dont turn out as you expect after an upgrade.

with your expirince you are probably the first to see this problem and equiped with the skills to solve it

regards peter

[mla]

Understood. I, on the other hand, am trying to point out that this is not always the best solution. Hence my bare-bones warning about akonadi, avoiding all assumptions.

And no, with my experience I shouldn't have missed the problem in the first place. Nobody's perfect.

Pax?