22C3 preparations

The main reason why this blog has been so quite since my return from Bangalore: I'm spending every free minute in preparations for 22C3, the annual Chaos Communication Congress. As usual, my job is to take care of the audio and video recording and streaming.

So for the last days I've been hunting numerous bugs related to this, mainly in ffmpeg, but also radeonfb, vlc, Debian ffmpeg / x264 packages, etc.

I'll be back on track after 22C3 is over. More blog updates then, I promise.

Documentation for GSM BTS arrived

Today I finally received PDF's of the Siemens BS-11 GSM BTS. This means that I'll now be able to actually connect the device to power, E1 and RS232.

Unfortunately I'm still lacking the configuration software for the device, and a corresponding E1 card for the Abis interface. Anyway, seems like we're slowly getting there. Maybe during Q1/Q2 2006 I can spend some time actually implementing code for that beast.

ulogd2 now has an abstract SQL/db layer

This means that there is now very little code duplication between the mysql and pgsql drivers, since all the high-level functionality is now 'abstracted away'.

libusb > 1.0.7 broken

Sometimes I really feel like I don't understand what's going on with some projects and/or developers. The last time I looked at libusb source code, it was the 1.0.7 release - and everything was working as expected. When you submit a bulk/interrupt read request, then it would do a blocking read until the user-specified timeout has expired.

When recently strace()ing a program using libusb, I found out that with my currently-installed version (1.0.10a), it actually does a non-blocking read (REAPNDELAY), then uses select to implement a 1ms sleep, and starts all over again until the user-specified timeout has expired.

This is really bad. Not only clutters it your strace output with lots of noise, but it actually uses CPU, wastes cache lines, and probably most importantly: eats battery on notebooks!

I'll ask the libusb folks what kind of madness this is. Probably it's time to publicize libausb at some point (the libusb-wrapper that I implemented for async URB handling in the ctapi-cyberjack drivers) - and which now uses a copy of the libusb-1.0.7 functions for blocking bulk read/write, too.

yum oom

This is in response to Oh my, this was from running yum update on a 2.6.13 FC3 system and had reached the transaction test but got OOM killed.:

I've seen this numerous times on FC3 (probably even older FC) systems, and no matter how large you make swap, it never really works. The only workaround I found is to manually split the update into tiny chunks, and then update those tiny chunks each itself rather than a full system-wide update.

New userspace-only driver for cyberjack e-com (0x100)

I've just checked in a userspace-only version of the cyberjack e-com (0x100) driver. This means that we'll finally be able to work around the many broken old (drivers/usb/serial/cyberjack.c) cyberjack drivers that almost all the distributions ship. Apparently almost none of them seem to bother merging upstream fixes into their trees.

One minor problem though is that both cyberjacks need asynchronous delivery of interrupt URB's, a feature that is not available by libusb. The libausb wrapper library that I developed for this purpose is specific to Linux usbdevio, so the userspace driver won't be working on other libusb supported platforms such as *BSD :(

FOSS.in is over

I'm not going to write any more about FOSS.in, since everyone else has already written about anything that there is to say. If you want to read all of it, go to planet.foss.in.

One fact that hasn't very much publicized [yet?] though, is the financial trouble that the event formerly known as Linux Bangalore is going through this year. This apparently is almost exclusively to blame at the sponsors (or lack thereof).

Apparently in India it's quite normal that even if you start talking with Sponsors more than half a year in advance, they will not commit until a few days before the event starts. This is also the reason why the conference programme is announced before the sponsors show up on the website (if you checked it before the event, all the sponsor banners were empty).

Due to this strange culture, it could happen that a large Indian IT company dropped their sponsoring commitment almost immediately before the event - that is _after_ the organizers having committed to all the expenses. I don't think that given those conditions, any organizer could have managed without a big large gaping hole in the budget :(

In addition to that, it is is a pity that none of the internationally recognized (and also locally quite present) "open source" companies Novell/SuSE and RedHat didn't show up on the sponsors list at all.

Report from FOSS.in 2005

This is the third day of FOSS.in 2005, for me it's the second day, since I arrived one day late.

I'm having a good time, and the conference has come quite some way since last years Linux Bangalore. To highlight some of the changes:

• Wireless Access almost everywhere on the venue!
• Enough halls (actually: tents!) to host BOF sessions and the like
• Lecture halls large enough to accommodate the whole audience
• A much wider scope, Free/Open Source software in general, rather than just Linux
• Lots of interesting presentations
• Way better quality of food (even though it wasn't really bad before)
• Sensible temperature instead of ridiculous amount of AC in lecture halls

Also, since the same amount of attendees are distributed over a wide area and more lecture halls, it is less crammed/crowded than the previous year. At least for people from a western country it therefore is way more relaxing, since there is more space between you and the people immediately surrounding you ;)