gnegg: July 2006

Nice summer

This is what the Bundesamt für Meteorologie und Klimatologie (basically the official entity to tell us and the world how the weather in Switzerland is) has to say about the upcoming weather.

It shows a certain nicety in this summer: It’s neither just hot (like 2003) nor just cold (like all other years for the last 10 years or so). There are hot days like last week, but there are also the cooler ones like just now where it’s raining at comfortable 22 degrees celsius.

And just when you have enough cool weather and want the sun back, it’s turning around again just to get colder when it’s getting too hot.

I wish every summer could be like this.

Computers under my command (2): marle

While everyone keeps calling her Marle, she is actually the princess Nadia of the Kingdom of Guardia in what many people are calling the best console RPG ever made, Chrono Trigger

Chrono Trigger was one of the last RPGs Squaresoft ever did for the SNES and it’s special in many ways: Excellent Music (by Yasunori Mitsuda), excellent graphics, smooth game play, really nice story and: Excellently done characters.

Robo, Frog, Lucca, Marle, Crono, Magus and Ayla – every one of them has its very own style and story. Aside from Crono which is quite the ordinary guy, every one of them is special in its own kind.

The server marle is special on its own way too.

It’s not as outstanding as shion, but it’s special in its own way: It was the first 64Bit machine running a 64Bit OS I’ve ever deployed.

The OS was Gentoo linux (as usual) and the machine itself is some IBM xSeries machine equipped with a 3Ghz Xeon processor and 2GB of RAM, so basically nothing you need 64 Bit for.

It still was an interesting experiment to get the machine to work with a 64 Bit OS, though all that went completely uneventful.

Ever since deployed, marle is running at a customers site without crashes or other problems.

marle ~ # uptime
     11:56:13 up 265 days, 44 min,  2 users,  load average: 0.00, 0.01, 0.00

Not much happening there currently I guess. Also, it’s amazing how quickly time passes – installing that machine feels like it was only yesterday.

More disk space needed

Can somebody explain me, why my Mac OS X needs 4 TB of diskspace to encrypt my home directory which currently is about 15 GB in size?

Before I got this message, it wanted me to free another 1KB, btw. When I did that and retried, this message popped up. Unfortunately, I can’t reproduce that other message though.

Computers under my command – Issue 1: shion

Picture of the "real" Shion Uzuki

After yesterdays fun with one of my servers, I thought I could maybe blog about some of them – especially when they are kind of “special” to me.

Of course, the first machine I’m looking at is my PowerPC Mac mini which I called “Shion”, after the girl Shion Uzuki of the Xenosaga trilogy.

I don’t really have a very advanced naming scheme for my servers, but the important ones get names I tend to remember.

First it was people from Lord of the Rings (with Windows servers having names belonging to the evil people). Then, after I ran out of names, it was places in LotR and after I run out of those too, I began naming (important) servers after girls in console RPGs.

And of all the names, I guess shion is a very fitting name for a server. In the game, Shion is a robotics engineer and the inventor of that android called KOS-MOS.

And in my network, shion has a special place:

I initially bought the machine to run a SlimServer on it as my previous NSLU solution was not really usable as hardware for the heavy, perl-based slim server.

After I replaced the slim-server, I obviously installed a samba server on shion to serve the non-music files as-well. Back then, I only had one external drive connected to the server.

Next thing to get installed was OpenVPN which I used for quite a nice configuration allowing me transparent access from and to the office.

Shortly after that, I finally found a USB ethernet adapter which made shion replace my ZyAir access point. I also had to buy a USB hub back then and I decided to use the remaining two ports of that to plug in additional hard drives, leading to shion’s current disk space capacity of roughly 1.2 TB.

Then I installed mp[3]act (I’ve also blogged about it) and shortly after replaced it with Jinzora due to mp[3]act being quite bug-ridden and not in development any longer. (update 2013: links removed – mp[3]act is now pointing to a porn site and Jinzora is gone)

In all that time (one year of operation), shion never crashed on me. Overall, the stability of my home network went through the roof since switching all tasks over to her: No more strange connection losses. No more rebooting router and cable modem when lots of outgoing connections are active. No more inexplicable slowness in the internal network.

Shion does a wonderful job for me and I would never ever go back to any less flexible or stable solution.

Lately, I thought about maybe ditching her for a more powerful intel-based Mac Mini, but in the end shion is fast enough for my current purpose and I could never ditch a machine as nice as this one.

Flexible, Stable, Fast, Quiet and quite inexpensive. A machine worthy of being referred to with a name and a female pronoun.

Linux, PowerPC, gcc, segmentation fault

If you ask of me me to name the one machine in my possession I love the most, that’ll be my Mac Mini.

It’s an old PPC one, I bought a bit more than a year ago with the intention of installing Linux on it and using it as home-server/router. It’s not the quickest machine there is, but it’s the most quiet and it does its job like no other machine I ever had: Its Samba file server, OpenVPN Gateway, bittorrent client, mp3 streaming server, SlimServer, just all you could ever use a home server for.

From the beginning, it was clear to me: The distribution I’m going to install on the beauty was to be Gentoo Linux. This decision was based on multiple reasons, from hard facts like always current software to soft facts like nice command-prompts.

Basically, the machine just sat there after I installed it, doing its job. Until this week when I wanted to install some software on it – mainly the unrar command to extract some file right on one of the external HDs I plugged in (shion – that’s what the machine is called – is connected to about 1TB worth of external HDs).

Unfortunately, emerge unrar failed.

It failed hard with a SIGSEGV in gcc (or its cousin cc1).

Naturally I assumed there to be some bug in the gcc I originally installed (3.3 something – as I said: I did not touch the installation for a year now) and I tried to reemerge gcc.

… which ALSO failed with a segmentation fault.

I had no interest what so ever in reinstalling the box – I invested much too much time in its configuration. Cron jobs here, certificates there, home grown scripts everywhere. Even with all the backups I had in mind – I did not want to do that kind of job. Besides: Who tells me if it’s really a software problem? Maybe the hardware is at fault which would mean that my work was in vain.

Searching for “gcc segmentation fault ppc” in google is… interesting… but not really something you can do if you actually want a solution for this problem.

In the end, I mentally prepared myself to go on with the reinstallation – still hoping it’d be a software problem.

And by accident, I came across the Gentoo PPC FAQ which I more or less read out of pure interest while waiting for the ISO to be burned.

To my biggest delight, said FAQ was really helpful though as it had a question that went “Why does gcc keep segfaulting during ebuilds?”

So it is a kernel problem! Of course I had preemption enabled! And that option – while working perfectly on all my x86 boxes – causes cache corruption on PPC.

Now that I knew what the problem was, I had two possible ways to go on: Quick and dirty or slow, but safe and clean:

Recompile the kernel on the obviously defective machine, hoping the cache corruption would not hit or at least would not lead to a non-bootable kernel to be compiled.
Boot from a Gentoo live-CD, chroot into my installation, recompile the kernel.

Obviously, I took the option 1.

I had to repeat the make command about 20 times as it continued to fail with a segmentation fault here and then. Usually I got away with just repeating the command – the cache corruption is random after all.

I was unable to get past the compilation of reiserfs though – thank god I’m using ext3, so I could just remove that from the kernel and continue with my make-loop.

Rebooting that kernel felt like doing something really dangerous. I mean: If the cache corruption leads to a SIGSEGV, that’s fine. But what if it leads to a corrupted binary? And I was going to boot from it…

To my delight, this worked flawlessly though and I’m writing this blog entry behind the rebooted MacMini-router. This time, even compiling the all new gcc 4.1.1 worked as expected, so I guess the fix really helped and the hardware’s ok.

Personally, I think fixing this felt great. And in retrospect, I guess I was lucky as hell to have read that FAQ – without it, I would have gone ahead with the reinstallation, compiling yet another kernel with preemption enabled which would have led to just the same problems as before.

Maybe the (very talented) Gentoo Hanbook guys should add a big, fat, red (and maybe even blinking) warning to the handbook to tell the user not to enable preemption in the kernel.

I know it’s in the FAQ, but why is it not in the installation handboook? That’s the place you are reading anyways when installing Gentoo.

Still: Problem solved. Happy.

SQLite on .NET CF – Revisited

Another year, another posting.

Back in 2004, I blogged about Finisar.SQLitem which at the time was the way to go.

Today, I am in quite the same situation as I was back then, with the difference that this time, it’s not about experimenting. It’s a real-world will-go-life-thing. I’m quite excited to finally have a chance at doing some PocketPC / Windows Mobile stuff that will actually be seen by someone else than myself.

Anyways: The project I blogged about is quite dead now and does not even support the latest versions of SQLite (3.2 is the newest supported file format). Additionally, it’s a ADO.NET 1.0 library and thus does not provide the latest bells and whistles.

Fortunately, someone stepped up and provided the world with
ADO.NET SQLite, which is what I’m currently trying out. The project is alive and kicking, supporting the latest versions of SQLite.

So, if you, like me, need a fast and small database engine for your PocketPC application, this project is the place to look I guess.