Markup language Updated +Created
TP Link ARCHER VR2800 router Virgin Media wifi Updated +Created
Printers Updated +Created
Internet speed Updated +Created
Home 2017 TalkTalk 38Mbps nominal, Google M-lab speed test:
  • 36.4 Mbps download
  • 9.15 Mbps up
  • 58 ms latency over 80km of first world
Mould Updated +Created
2019-12-26: applied Ronseal mould killer on external north east living room walls, had widespread light brown mould spots, and more localized black mould spots. The water insulation here is bad, possibly due to being on the last floor. Also applied next to window sills on those walls.
Lenovo ThinkPad P14s gen4 amd Updated +Created
Bought: November 2023 during Black Friday sale for £1,323.00 to be Ciro Santilli's main personal laptop.
Six years after, and we are 2x on every key spec (except processor Hz ;-) at about 1/2 the price and 1/2 the weight (though smaller 14" screen for greater portability), so not bad! Customized to max out each hardware spec:
Specs:
  • Processor: AMD Ryzen™ 7 PRO 7840U Processor (3.30 GHz up to 5.10 GHz)
  • Operating System: No Operating Systemselected upgrade
  • Operating System Language: No Operating System Languageselected upgrade
  • Microsoft Productivity Software: None
  • Memory: 64 GB LPDDR5X-6400MHz (Soldered)selected upgrade. Specs at: www.lenovo.com/gb/en/p/accessories-and-software/memory-and-storage/memory-and-storage-hard-drives/4xb1d04758 quotes "64 Gbps", i.e. 8 GB/s. dd count=1M if=/dev/zero of=tmp gives only 255 MB/s however.
  • Solid State Drive: 2 TB SSD M.2 2280 PCIe Gen4 Performance TLC Opalselected upgrade
  • Display: 14" WUXGA (1920 x 1200), IPS, Anti-Glare, Touch, 45%NTSC, 300 nits, 60Hz
  • Graphic Card: Integrated Graphics
    The Ubuntu 23.10 "About system GUI describes its graphics as: Radeon 780M Graphics × 16, which e.g. www.techpowerup.com/gpu-specs/radeon-780m.c4020 documents as running the RDNA 3 microarchitecture.
  • Camera: 1080P FHD RGB/IR Hybrid with Microphone
  • Color: Thunder Black
  • Factory Color Calibration: No Factory Color Calibration
  • Wireless: Qualcomm Wi-Fi 6E NFA725A 2x2 AX & Bluetooth® 5.1 or above
  • Integrated Mobile Broadband: No Wireless WAN
  • Ethernet: Wired Ethernet
  • Near Field Communication: No NFC
  • Fingerprint Reader: Fingerprint Reader
  • Keyboard: Black - English (EU)selected upgrade
  • Battery: 4 Cell Li-Polymer 52.5Whselected upgrade
  • Power Cord: 65W USB-C Slim 90% PCC 3pin AC Adapter - UKselected upgrade
  • Electronic Privacy Filter: No ePrivacy Filter
  • Adobe Elements: None
  • Adobe Acrobat: None
  • Adobe Creative Cloud: None
  • Security Software: None
  • Cloud Security Software: No Cloud Security Software
  • Warranty: 3 Year Courier or Carry-in
Identifiers:
Upon arrival:
  • Weight: 1490 g
  • Charger weight: 323 g
  • Firmware according to sudo dmidecode -t bios:
    Vendor: LENOVO
    Version: R2FET33W (1.13 )
    Release Date: 09/08/2023
Buy research:
Log:
2024-01-17: firmware update:
Vendor: LENOVO
Version: R2FET36W (1.16 )
Release Date: 10/24/2023
Actually fixed performance mode: askubuntu.com/questions/604720/setting-to-high-performance/1343879#1343879
Lenovo ThinkPad P51 (2017) Updated +Created
Bought: 2017 for approximately 2400 pounds to be Ciro Santilli's main personal laptop.
Specs:
  • screen: 15.6 inches, 16:9
  • weight: 2691g (self weight in 2023)
  • charger weight: 700g (self weight in 2023)
Identifiers:
Raspberry Pi Pico W Updated +Created
With pre-soldered male pin headers.
>>> machine.unique_id()
b'\xe6ad\x08C8%$'
Raspberry Pi 2 Updated +Created
As of 2018-12, I believe that I might have fried the UART on this board when I burnt my last UART to USB converter by connecting ground to 5V.
Linux kernel logs don't show, but do show with the exact same components on the Pi 3 (SD card with enable_uart=1 + image Raspbian Lite 2018-11-03 and UART cables).
Serial from cat /proc/cpuinfo: 00000000a50c1f69
Datasheets: Raspberry Pi 2.
Fire alarm Updated +Created
2021-08 bedroom battery out, 7.29V out of 9V duracell duralock. Buying pack of 12 Energizer nine-volt batteries. Measurement on new battery: 9.68V.
Dell Inspiron 15 3520 Updated +Created
Bought May 2024 to be my clean crypto-only computer. Searched for cheapest 1 TB disk 16 GB RAM not too old on Amazon with Ubuntu certification, and that was it at £479.00.
Some reviews:
  • the keyboard is kind of crap. Notably the key "a" is very hard to press!!
  • the lack of a sleep state indication LED and "I'm powering on LED" compared to Lenovo is really sad
  • it gets way too hot doing work (Monero bootstrap) with lid closed, likely brought system down
OPSEC: will run only cryptocurrency wallets and nothing else. Will connect to Internet, but never ever to a non clean USB flash drive.
The OPSEC for this machine supposes:
  • no supply of chain attack on USB hardware, Laptop hardware, pre-installed Windows and Ubuntu ISO
  • connecting with browser to a few well known websites to download stuff (Ubuntu ISO, Monero software) is safe
Bootstrap OPSEC:
It must have taken about one week running full time to sync the Monero blockchain which at the time was at about 3.1M blocks! I checked on system explorer, and CPU and internet usage was never maxed out, suggesting simply slow network. But the computer still overheated quite a bit and froze a few times.
Nike Run Swift 2.0 Updated +Created
Bought 2021-11, grey, size EUR 44.5, 80$ (later found cheaper online): www.sportsdirect.com/nike-run-swift-2-running-shoes-mens-121052
Ciro Duran Santilli Updated +Created
Ciro Santilli's full birth name is "Ciro Duran Santilli", with mother's last name "Duran" in the middle as per Brazilian tradition.
But Ciro's usage of "Duran" got gradually dropped to "Ciro Santilli", Ciro's official Italian name, as Ciro moved more and more definitively to Europe.
It can still however be seen in certain online places where Ciro didn't have the patience or power to change it e.g. some old École Polytechnique stuff: gitlab.binets.fr/ciro.duran-santilli/china-dictatorship
Also, don't have multiple names if you can avoid it, it is confusing!
"Weird Al" Yankovic Updated +Created
Holomorphic function Updated +Created
Being a complex holomorphic function is an extremely strong condition.
The existence of the first derivative implies the existence of all derivatives.
Another extremely strong consequence is the identity theorem.
"Holos" means "entire" in Greek, so maybe this is a reference to the fact that due to the identity theorem, knowing the function on a small open ball implies knowing the function everywhere.
Imaginary unit Updated +Created
Cayley-Dickson construction Updated +Created
Constructs the quaternions from complex numbers, octonions from quaternions, and keeps doubling like this indefinitely.
Whole organism simulation Updated +Created
How computers work? Updated +Created
A computer is a highly layered system, and so you have to decide which layers you are the most interested in studying.
Although the layer are somewhat independent, they also sometimes interact, and when that happens it usually hurts your brain. E.g., if compilers were perfect, no one optimizing software would have to know anything about microarchitecture. But if you want to go hardcore enough, you might have to learn some lower layer.
It must also be said that like in any industry, certain layers are hidden in commercial secrecy mysteries making it harder to actually learn them. In computing, the lower level you go, the more closed source things tend to become.
But as you climb down into the abyss of low level hardcoreness, don't forget that making usefulness is more important than being hardcore: Figure 1. "xkcd 378: Real Programmers".
First, the most important thing you should know about this subject: cirosantilli.com/linux-kernel-module-cheat/should-you-waste-your-life-with-systems-programming
Here's a summary from low-level to high-level:
Figure 1.
xkcd 378: Real Programmers
. Source.
Video 1.
How low can you go video by Ciro Santilli (2017)
Source. In this infamous video Ciro has summarized the computer hierarchy.

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