Centroid.EU Blog

(this blog is mostly encrypted - adults only)

I'm a hoarder and I'm a tech hoarder

February 12th, 2021

At home I rarely like to throw things out. Like recyclable garbage. I want you to take a look at this youtube clip (linus tech tips) can you identify yourself with this persons household? If you can, you're like me too. I stopped counting how many things I have with a CPU chip, (over 15?). On top of that I see a couple burned out lightbulbs in front of me, why haven't I thrown them out? Well for one I'm confused on the recycle policy, so it's still here. I have a lot of cardboard from amazon purchases too but I did throw out the styrofoam in them. I don't think this is a mental illness it has to do with my genes somehow, that would make you and I similar if you too are a hoarder. I have a broken ipod, why don't I throw it out? Because it may contain private things that another guy with clue can unlock and use. This is my train of thought. While I do feel a bit sorry for myself in this I think there is more to this story.

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Grafenrheinfeld Reactors hold no fuel anymore

February 10th, 2021

According to this (german) the fuel rods have all been removed from the local nuclear fission reactor, which was closed down in 2015. Oh my goodness it took almost 6 years! My question that I'll shoot off into the ether is, when will they wreck the towers and buildings? What will become of the site? How much longer will nuclear waste be held there? Will nuclear waste from other power stations be held there? These are all questions that make me go hmmm. I had seen job openings of companies that are near there, but because of their close vicinity to this nuclear site I did not want to work there. Basically the sooner it's gone the better. Erect a wind or solar park there or something, I wouldn't want the site be used for anything else. Also see the following articles here: good weather ahead?.

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Goal for the next 2 years - a RPI cluster

February 7th, 2021

I'm considering making a 6-8 node raspberry pi cluster. This is with a RPI 4b - 8 GB or better category SBC's. The idea was born a few years ago. So, if I'm in employment in 2 years I'll fulfill this, otherwise I'll be short on pi's. We'll see. RISC-V is taking off so I'll see if I can get some RV SBC's instead of Raspberry Pi's if they are worth getting. It stays fun either way!

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35 Years of Personal Computing History

February 7th, 2021

Here is a list of computers I had the pleasure of purchasing before 2020

2x Intel P-II-350,1x Sinclair ZX-81,1x PC-Engines APU 4,1x PC-Engines APU 2, 1x Intel Xeon E3-,1x Intel Pentium 200,1x Intel Pentium 120, 1x Intel Core i7 4core,1x Intel Atom N270,1x IBM-PC 486-66DX2, 1x IBM-PC 386-SX25,1x Commodore C-64,1x Celeron CPU N2940,1x Apple Mac mini, 1x Apple MBP Core i5,1x Apple G4 Cube,1x Apple G3 iBook,1x AMD C-60 "Ontario", 1x AMD Athlon64 3500+,1x AMD Athlon 1000, 1x Core i3 NUC, 1x Core i3 Workstation 1x Apple G5 PowerMac

The approximate aggregated clockspeed was 60000 MHz and aggregated memory was roughly 100 GB. 2021 marked 35 years of personal computing history.

Computers since 2021 I have received or purchased:

Type			Clockspeed	Agg Clks	RAM		Agg RAM
-------------------------------------------------------------------------------
1x Raspberry Pi 4B, 	4x 1.4 GHz, 	5600 MHz,	8 GB RAM,	8 GB

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Thinking of GAIA Blobs

February 6th, 2021

I have this crazy idea to make a distributed database of GAIA DR2 data (roughly 600 GB). The data (a record or star) looks something like this and this is the wc count (496 bytes) of it:

uranus$ gzip -c | wc
1635721458409799680,Gaia DR2 1000098115720057600,1000098115720057600,1361854776,
2015.5,103.1447687171818,0.8780932883857252,55.66026380549414,0.7278023692495272
,-1.0492303789045414,0.9531253833899975,-1.1008314,-1.016497904185785,1.72718979
95209469,-0.999969469190631,1.4027991475275494,0.37339288,-0.017223373,-0.434678
67,-0.20079584,0.11420303,-0.09444078,-0.148463,0.31253383,0.10378465,0.5487187,
139,0,138,1,-0.45912188,125.01081,0.0,0.0,31,false,0.030090865,1.277746149365293
5,0.24892326177107457,-0.03192049,17,11,1.7869129,0,17,false,140,115.54664634249
542,1.4401741227750422,80.231026,20.531473,12,61.96995745461367,6.93235374293182
,8.939238,20.870935,13,86.057918036162,7.674608860147498,11.213329,19.924942,1.2
811092,0,0.9459934,0.33946228,0.60653114,,,0,,,,NOT_AVAILABLE,160.49033861944486
,22.272304438623387,98.76067525889512,32.620037156450245,,,,,,,,,,,,,,,,,^D
       0      10     496

Noncompressed the data is about 884 bytes. I'm thinking of sticking this into DNS data as a compressed blob that is then uuencode which is roughly 675 bytes.

I'm envisaging this entire data being split up and distributed around 864 cities in the EU. So that when you query the entire database it has 864 sources to answer from via the Internet. The data may get cached in DNS servers too speeding lookup. I know a DNS person would look at me weirdly and caution not to put everything in DNS but this is for our stars in the galaxy! Surely it's good data. Transport would be over UDP for small records but there could be records that are huge. I envisage up to about 100 GAIA blobs served over TCP. Anyhow, when I have the protocol implementation I'll approach some astronomical societies and pitch it to them. Perhaps in the next 2-3 years.

Once the distributed database is built, it can be used by astro software for cross-referencing. These are in-memory databases only. I figured 800 odd raspberry pi 4b's with 8 GB RAM would be enough. I can't shoulder this cost alone but if everyone chips in it's manageable.

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New Transatlantic cable owned by Google

February 4th, 2021

This 250 Tbit/s cable is privately owned by Google. It's amazing high capacity, at least to me.

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Making my C Primer available to all

February 3rd, 2021

Between 2004 and 2017 I wrote on a C primer at hackepedia. Then I took that and formatted it nicely and corrected it a little bit.

I'm making it available for the first time here. Enjoy!

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3 months "Funkstille"

February 2nd, 2021

After three months of no word from arbeitsagentur.de I got an automated mailing from them again with a job recommendation. It looks as if they changed a flag on my profile. Wonder what's up with that.

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14 days away from 8 years in this apartment

January 31st, 2021

On Feb 13th, 2013 I moved into this apartment. It will be eight years soon, and it's the longest time I've been anywhere in my life in one length. However I don't know if I'll have a ninth year here, I've signed up for looking for a new smaller flat after easter. Hopefully it will be near this area. Times are rougher for me now than they were eight years ago, but I'm hanging in there. Hopefully I'll find a real good work soon so that I can have an outlook on my remaining life. I'm turning 45 years old in March.

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Starlink Internet...back to Internet Cafe's?

January 30th, 2021

The other day I was watching a very informative youtube report from an indian lady. She made me aware that a starlink sat can only throughput/relay about 20 Gbit/s (not sure where that number comes from but let's go with it). Then if starlink satellites are 1000 km spaced apart in orbits covering the USA, that means there is only 5 coast to coast, in 3 rows so 15 satellites over the USA at any point in time. So let's crunch the numbers: (15 * 20Gbit/s == 300000 Mbit/s) which has customers downloading at 150 Mbit/s which is 2000 user terminals USA wide. But all internet is oversold and after loading a webpage there is some pause. So let's say you can have a user ratio of 10:1, that's 20,000 terminals/dishys on earth. At this rate it becomes clear that the "other 40%" of Internet users won't be reached. The lady goes on to say that other data plans are likely. So 15 Mbit/s perhaps. That would put it in the range of other satellite operators and 200,000 users in the USA. So SpaceX has to either increase the capacity on the satellites (> 20 Gbit/s) or run more satellites through the USA (in orbit).

Let's look at what starlink is good at. Low latencies. This means that predominantly VOIP can profit off a starlink but a large download probably not so much, large downloads can probably be done on high latency links. Fortunately a phone call is only about 100Kbit/s or so, and that's a high quality phone call. This means you can have a datacenter of around 150 telephone operators at 15 Mbit/s, if you want data then you probably will have to buy more capacity. Let's look at starlink on a sub-continent like India. India is a lot smaller than the USA and there may only be 5-6 satellites above it at any given time. And this is where I envision Internet cafes popping up again utilizing starlink. In fact did Internet cafes ever really leave Asia? Internet is still rare in such places thus it may make sense to smartly use Internet differently. Perhaps one or two starlink uplinks and a wifi-mesh for open community networks?

I'd get starlink but I don't really need it. The highest bandwith I can get at home is 250 Mbit/s VDSL (cable can't come into my building otherwise it'd be higher), and I'll likely stick with the VDSL as long as I have this apartment. As a backup link I use the vodafone flex package. It means I don't pay until I use it. And i haven't used it in at least a few dozen months. When I used it I got 7.5 Mbit/s last over LTE. Unless vodafone did some upgrades in the last two years that is what I expect it to be. I will only pull it out until I really need it. ie. longer power outtages or me moving apartments which may mean some downtime from Internet. I'm very happy though that I'm making bandwidth for the next person in a village not far from me that has a 8 Mbit/s download only he or she may need starlink more than me.

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