It’s a libcairo2 1.12.2-2 issue – which you can thankfully fix by downgrading libcairo2 to a 1.10.2 incarnation – here’s how…
Check package availability
First check you have an alternate version to downgrade to. To do this in Synaptic select the libcairo2 package then click on the Versions tab at the bottom, or you can do the same check via a swift apt-cache policy libcairo2 as shown below:
I’m working my way through C++ FAQs book by Cline and Lomow, and it’s excellent. There’s lots of issues going on with inheritance, arrays and casting that could be a real pain to deal with towards the end of system development, but that you can nip in the bud and make life easier for yourself. For example, just knowing that an array of objects of a Derived class is NOT a kind-of array of objects of the Base class can prevent you a lot of headaches…
// Book: C++ FAQs by Cline & Lomow
// FAQ 136 & 137 - Is array-of Derived a kind-of array-of Base?
Just noting this for future reference, but I finally got iTunes working properly on a Windows PC that would at random:
– transfer some songs to iPod Touch devices successfully,
– transfer some other songs, then crash, then the device reports no music on it, or
– corrupt the device so badly it needed fresh firmware restored.
And the the culprit turned out to be…. Zone Alarm. No kidding. Turn off Zone Alarm and everything worked instantly.
iTunes is still a god-awful PoS though, but at least it’ll now transfer music and apps. If you’re getting “app could not be installed because it is not signed” issues with iTunes, and you’re installing legit apps, chances are that turning off Zone Alarm will fix it right up. Amazing.
Just because all GNU/Linux distros come with a kernel, it doesn’t mean that it’s the best kernel to use. This was made quite clear to me recently when I discovered that whenever I safely removed a USB drive from my machine it caused a kernel panic in the present LMDE kernel (22.214.171.124) which promptly hung the machine. I figured out I could work around the issue by unmounting USB drives through gparted, but that’s pretty weak sauce, so I decided to cut to the root of the problem and change kernels.
In the past I’ve spent a long time picking specific kernel options, building the kernel, and then it hasn’t worked at all – so this time I wanted something I was pretty sure would work, and I didn’t want to spend forever on it, so what are the options?
Zen and the art of kernel maintenance
The official Linux kernel lives at kernel.org, and is the reference design if you will for all existing kernels. The new stuff generally gets added to the mainline kernel, and then other kernels add or remove bits and pieces to become their own kernels such as the Ubuntu kernels or the Debian kernels or what have you.
The process of adding or removing bits and pieces is pretty much open ended, and if you don’t know exactly what you’re doing you can spend a long time reading and experimenting, so I’ve opted to pick something pre-customised from the Zen kernels:
The Zen Kernel is a the result of a collaborative effort of kernel hackers to provide the best Linux kernel possible for every day systems. We include code that is not included in the mainline kernel in an attempt to create an all-around better kernel for desktops (although it can be compiled otherwise). This is done by including new features, supporting latest hardware, and including various code and optimizations to better suit desktops. Zen is a 100% community oriented project so, as a result, everybody can contribute to the project.
Who mods the modders?
A chap going by the handle of Damentz, who seems to have the black art of kernel crafting down to a tittle, takes that zen-kernel source and (I think) tweaks it some more to produce the Liquorix kernel.
What does he do exactly? I’ve absolutely no idea – maybe it’s in the forums somewhere, but I think the main thing he does is make it compatible with Debian, and provide a repository so we can grab and use his pre-built pre-modded zen kernel on Debian or any Debian-compatible distro such as LMDE. He’s also nice enough to build both 32-bit and 64-bit kernels so the repo should provide whichever version is appropriate for your system at install time.
Installing the liquorix kernel
Note: It’s a really good idea to make sure you have the dkms package is installed at this point so that any proprietary third-party kernel modules like graphics card drivers (nvidia/ati official drivers), virtualbox modules etc. get rebuilt as part of the kernel install.
1.) Add the liquorix repository to your apt sources file at /etc/apt/sources.list:
deb http://liquorix.net/debian sid main
2.) Update your system package list:
3.) Get and install the liquorix repository key to authenticate the packages:
4.) Install the liquorix kernel and header sources (you’ll want the sources so that DKMS can automatically rebuild kernel modules for you as required when you update the kernel) – it’s probably best to do this through synaptic/package manager so you can see what’s there:
Apart from the keys for package authentication, you really just need the linux-image-liquorix-amd64 and linux-headers-liquorix-amd64 meta-packages (or suitable 32-bit versions) which will then drag in the most recent version of the kernel, whatever that happens to be at the time.
While the packages are installing it’s best to keep an eye on the output to ensure that your dkms modules successfully rebuild – but as long as you’ve opted to install the kernel headers package along with the kernel there shouldn’t be a problem – it’s just nice to be confident that when you reboot you’re not going to be booting into a black screen with a flashing white cursor…
Reboot and choose your new kernel from the grub boot menu! (it’ll be the new default). Once you’re up and running you can always run uname -r or uname -a to confirm your kernel version, then take that bad-boy for a spin…
I only installed mine this morning, but the first thing I did was mount and then unmount a USB drives – and what happened? It kernel panicked. Turns out that the bug seems to be quite widespread among distros (Debian Bug 631187), but you can work around it by manually unmounting using umount (or by using gparted, as I found).
Still, it’s a new, multimedia/gaming optimised kernel (3 series, no less!) – which has its faults, but it seems a lot of kernels at the moment do, and it looks like I’d have to go back to 2.6.38.something to find a kernel which hasn’t had this bug introduced.
I’ve read good things about zen kernels in the past, so I’m glad to finally run one. Once I’ve had a chance to play around with it and that unmount wrinkle’s ironed out I’m sure it’ll be a nice, responsive kernel. And if it isn’t, then I’ll write another post that calls it names =P
Update 21/09/2011: I’ve read on the Liquorix forums that DKMS is not a great package, and although it might do useful things, it does them in bad, non-standard ways, so they highly recommend you uninstall DKMS entirely, and install things like graphics drivers and wifi drivers from the manufacturer’s sites directly (using sgfxi) because if DKMS screws it up, it can get pretty scrappy to fix.
I’ve tried for months to get along with the standard desktop choices for Ubuntu 11.04, but none of the “big 3” are doing anything close to what I want:
Unity crashes. A lot. And I don’t like having to click on an application icon multiple times to get a display of all open windows and then have to click on the window I want. For example, if you have multiple browser windows open, it just seems to pick the first one or a random one (as opposed to the last window of that application which was open) when you click on on the Unity icon for the app. And that sucks. I do like the menu integration into a single panel to save vertical space – but asides from that it’s just subpar.
Gnome 2 doesn’t frickn work properly anymore and also crashes a lot (far worse than ‘back in the day’, and Deskbar doesn’t work anymore either), and finally
KDE3 renders fonts really badly (yes, I did turn on and experiment with the sub-pixel hinting options) and although it can look quite nice, it just feels like a bodge. I spent hours trying to configure it properly and it was never as good as stock Gnome even after all the extra effort.
So, what options are left? Well, there’s LXDE (the Lightweight X Desktop Environment), and there’s XFCE (which Linus Torvalds recently switched to because he’s hating the desktop brokenness as well). I installed LXDE on my work laptop earlier, and there’s nothing particularly wrong with it which couldn’t be fixed up , but I installed XFCE earlier on the assumption that Mr. Torvalds knows what he’s talking about – and you know what? He does…
Some notes for if you decide to try out LXDE
In LXDE wireless networking doesn’t work right off the bat, so you might want to grab a copy of wicd before you plunge headfirst. Also, compositing isn’t natively supported with just LXDE, so you’ll also want a copy of xcompmgr, which you should kick off like this:
You can man xcompmgr once it’s installed to get all the switches, but for this example it just fades windows in and out nicely – and actually looks rather nice (not to mention blazingly fast).
I like LXDE, and if XFCE didn’t exist I’d use it without hesitation and be perfectly happy with it. Only XFCE does exist – and I choo-choo-choose that – at least for now. I also like the huge range of packages available for any *buntu, so that keeps me from jumping ship entirely. At the end of the day, it’s all up to personal choice about what features you absolutely must have, what features you would like, and your own personal preferences.
Step 1 of 1 – Install xubuntu-desktop
If you like dockbars you can use docky with XFCE without any arguments, but I kinda prefer a bottom ‘window-icon’ panel (ala Gnome 2) so I’ve just set things up that way on mine. And the entire thing goes on fine with the following simple command:
sudo apt-getinstall xubuntu-desktop
It’ll drag in a whole heap of other dependencies, but it’ll all install nicely, at which point you just need to log out and log back in selecting Xubuntu Session as the desktop environment to use. Wireless networking worked straight away with no hassle for me, but in all fairness to LXDE, I only installed the LXDE package (and its immediate dependencies), and not the lubuntu-desktop package which (may) have straightened all that out.
The end result
After looking through the themes, adding a few bits and pieces to the top panel, and creating a separate bottom panel for the window-icons, this is what I’ve ended up with:
Honestly though, I just couldn’t go on using a desktop environment that would crash if not once per day, then many times per day. I mean, really – WTF is with that? Why would you even ship a desktop windowing environment in that state? Since I actually like to get some work done and not have to be killing and relaunching processes all the time, XFCE is officially doing it for me at the moment. So no more unity –replace, s’long killall nautilus and sayonara panel has stopped responding – it’s time to be able to actually concentrate on getting some work done.