Rzip - A new compression star is born

Remember when Bzip first came out and out-compressed Gzip\? Well, then came LZMA with another significant increase in compression ration a bit later. And then one of the authors of Samba, Andrew Tridgell, developed a new compression algorithm called Rzip. It compresses even more efficient, though it needs large amounts (may be 1 GB) of memory to do so. And now Con Kolivas, author of the great Desktop Latency patches including the BFS scheduler and the man who designed the current kernel scheduler (though another implementation of his design was used), took it to himself to further develop the rzip algorithm. And the results are quite promising: The linux kernel is compressed about 3 times as fast as with LZMA2 with just 2 percent difference in final size. I look forward to this going downstream into end-user desktop software.

Update: Con just commented with a link to more detailed and accurate lrzip statistics.

Is the Linux Desktop getting slower and more bloated?

In his "failure of logic" post "K. Mandla" writes that the Linux Desktop is not getting faster even though all the hardware around it is getting faster, pointing to an article with the same argument 10 years ago. The ensueing discussion was much too abstract for my taste. ("Why are clouds?" "What clouds, where?") But if you split up the question you get answers:

Why Not Scale the CPU on Schedule?

Usually e.g. CPU frequency scaling works mostly by seeing how much of the CPU is utilized and then reacting by setting the frequency to a certain level to satisfy this need. But why not at least in addition introduce an interface for some software, e.g. media players, to inform the kernel up front how much CPU it will need. Then it the CPU will be available on time.

0.4 Watt Less During Audio Playback - (Updated:) Power Performance: Pulseaudio + Interrupt-Less Alsa

(Skip to the update)
Ok, so with some help from Pierre-Louis from Intel I've managed to get it working and do some performance/power tests. But let me start at the beginning: Recently, pulseaudio not only switched to a more power efficient (and otherwise) timing system, as far as I understand a callback API. It also provided the infrastructure to use ALSA devices without causing any interrupts ("period wakeup disabling"), so you CPU can stay longer in standby mode (e.g. "C6 residency"), saving you power and avoiding playback glitches at the same time. See here and here or more background information. With kernel 2.6.38 the first driver (snd-hda-intel) supports this infrastructure out of the box, the snd-hda-intel driver. This combination is what I tested for power efficiency...

The Linux Kernel Trojan Horse Gift

Linus describes how he prefers new features to be introduced to Linux:

In other words, every new crazy feature should be hidden in a nice solid "Trojan Horse" gift: something that looks _obviously_ good at first sight.

The fact that it may contain the germs for future features should be hidden so well that not only is it not used as an argument ("Hey, look at all those soldiers in that horse, imagine what you could do with them"), it should also not be obvious from the source code ("Look at all those hooks I sprinkled around, which aren't actually used by anything, but just imagine what you could do with them").

New Open Source Poulsbo Driver in 2.6.39 staging

It works pretty nicely - though just as a framebuffer device so far. A specialized Xorg userspace driver for the new staging kernel driver is expected sometime soon. It already supplies KMS and can be used with the fbdev driver of Xorg. So next time you want to try a new kernel you can at least get into a working X without much ado. And there will surely be at least a simple driver coming with new kernels now. The first steps have been taken. And of course, all this is hopefully just the beginning...

Samsung Galaxy Kies Connection and Upgrade Fails with MTP Device Driver Popup

If you can't connect your phone to Kies because there is a constant Windows popup saying that the mtp device is installed again and again or not working correctly, here's a great workaround. It's extremely easy and works perfectly for upgrading to the newest Android version:

Simply Eject the Flash Card. Then connect the phone and it all works fine. Of course this way it can't access the SD card. And there will be a popup saying that the sd card is not inserted, just ignore it! ;)