Book Review: The Supermen – The Story of Seymour Cray

Back in the mid 1980’s I’ve visited my uncle at the ETH Zürich and I still remember what he showed to me that day: A Cray-1 supercomputer. There I was, a teenager with a Commodore 64 at home standing right next to one of the fastest computers on earth at the time. The very fact that I still remember the visit is a strong indication that it had a long lasting effect on me and certainly influenced my future. Now, 30 years later, I thought it was time to revisit this piece of my past and learn a bit more about it.

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OpenVPN Throughput Revisited

I’m using OpenVPN for many years now and while in the past the uplink speed of my DSL connection at home was the limiting  factor when it came to throughput, this might not be the case anymore. I was therefore keen to check if my current OpenVPN setup in a virtual machine on an Intel i3 based server can still handle the theoretical maximum throughput of 35-40 Mbit/s, which is the uplink speed of my vectorized VDSL line.

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Power Charging Investigations

Back in 2014 I noticed for the first time that different devices charge at different rates on the same charger. At the time I had a Samsung charger that could supply 5 V and 2 A and even then, devices such as the Samsung Galaxy S4 made good use of it by drawing 1.6 A. A bit down the road, a new device I bought came with a power adapter that could either supply 2 A at 5 V or 1,67 A at 9 V. So do devices I have actually make use of this?

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Evolution of International Roaming Prices

10 years ago, most people would have deduced from the headline of this post that I would probably want to talk about prices for voice calls while roaming. Today in 2018, I’m pretty sure most people will think about Internet access first. And indeed, I am in the US at the moment and I have noticed that my German network operator of choice has a new data roaming offer for North America that goes beyond what was available so far. This inspired me to have a look at how things have evolved over the past decade.

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Book Review: The Time Machine

I like to read literary classics every now and then but recently, I’ve been somewhat hindered by Project Gutenberg completely blocking German visitors after a German court has ruled that they must not make certain works available in Germany. Shame on the S. Fisher publishing house and I will certainly never buy anything from them again.

In any case, there are ways around the embargo, so when a short vacation came up, I made good use of the platform and downloaded a couple of books, including H. G. Wells’s ‘The Time Machine’.

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LineageOS on a Samsung Galaxy S9

Over the years, I’ve used LineageOS and its predecessor CyanogenMod on my personal devices such as the Samsung Galaxy S4 and, for the past few years, on the Samsung S5. But my S5 is aging so I was looking for a replacement. There is a LineageOS port for the Galaxy S6 but it seems to be quite experimental, I kept having power drain issues due to some system task starting to run wild after a few days. There’s also a version for the Galaxy S7 which is already kind of hard to get on the market but a version for the S8 is missing. The more surprised I was to see that there is a version for the relatively recent Galaxy S9.

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