Place and route by Ciro Santilli 40 Updated 2025-07-16
Given a bunch of interlinked standard cell library elements from the logic synthesis step, actually decide where exactly they are going to go on 2D (stacked 2D) integrated circuit surface.
Sample output format of place and route would be GDSII.
Verilog by Ciro Santilli 40 Updated 2025-07-16
Examples under verilog, more details at Verilator.
riscv/timer.S by Ciro Santilli 40 Updated 2025-07-16
Tested on Ubuntu 23.10:
sudo apt install binutils-riscv64-unknown-elf qemu-system-misc gdb-multiarch
cd riscv
make
Then on shell 1:
qemu-system-riscv64 -machine virt -cpu rv64 -smp 1 -s -S -nographic -bios none -kernel timer.elf
and on shell 2:
gdb-multiarch timer.elf -nh -ex "target remote :1234" -ex 'display /i $pc' -ex 'break *mtrap' -ex 'display *0x2004000' -ex 'display *0x200BFF8'
GDB should break infinitel many times on mtrap as interrupts happen.
In v4.2, look under arch/x86/:
  • include/asm/pgtable*
  • include/asm/page*
  • mm/pgtable*
  • mm/page*
There seems to be no structs defined to represent the pages, only macros: include/asm/page_types.h is specially interesting. Excerpt:
#define _PAGE_BIT_PRESENT   0   /* is present */
#define _PAGE_BIT_RW        1   /* writeable */
#define _PAGE_BIT_USER      2   /* userspace addressable */
#define _PAGE_BIT_PWT       3   /* page write through */
arch/x86/include/uapi/asm/processor-flags.h defines CR0, and in particular the PG bit position:
#define X86_CR0_PG_BIT      31 /* Paging */
Erase SSD securely by Ciro Santilli 40 Updated 2025-07-16
You can't just shred individual sSD files because SSD writes only at large granularities, so hardware/drivers have to copy stuff around all the time to compact it. This means that leftover copies are left around everywhere.
What you can do however is to erase the entire thing with vendor support, which most hardware has support for. On hardware encrypted disks, you can even just erase the keys:
TODO does shredding the
pciutils by Ciro Santilli 40 Updated 2025-07-16
Sotware project that provides lspci.
History of Google by Ciro Santilli 40 Updated 2025-07-16
The 1997 Wayback Machine archives are just priceless: web.archive.org/web/19971210065425/http://backrub.stanford.edu/backrub.html. I'm so glad that website exists and started so early. It is just another university research project demo website like any other. Priceless.
In August 1998 they had an their first investment of $100,000 from Andy Bechtolsheim, Sun Microsystems co-founder. Some sources say September 1998. This was an event of legend, the dude dropped by, tested the website for a few minutes, said I like it, and dropped a 100$ check with no paperwork. Google wasn't even incorporated, they had to incorporate to cash the check. They were apparently introduced by one of the teachers, TODO which. Some sources say he had to rush off to another meeting afterwards:
Tried to sell it for 1 million in early 1999... OMG the way the world is. It would be good to learn more about that story, and when they noticed it was fuckup.
One of Google's most interesting stories is how their startup garage owner became an important figure inside Google, and how Sergei married her sister. These were the best garage tenants ever!
Video 1.
Andy Bechtolsheim's 100.000 check by Discovery UK (2018)
Source. Contains interviews with Andy Bechtolsheim and David Cheriton. The meeting happened in David Cheriton's porch. Andy showed up at 8AM, and he had a meeting at 9AM at Cisco where he worked, so he had to leave early. Andy worked at Cisco after having sold his company Granite Systems, which David co-founded, to Cisco. Particularly cool to see how Andy calculated expected revenue quickly on the back of his mind.
Video 2.
Larry Page interview on the choice of name "Alphabet" by Fortune Magazine (2015)
Source. Shows his voice situation well, poor guy.
LSF get version by Ciro Santilli 40 Updated 2025-07-16
Most/all commands have the -V option which prints the version, e.g.:
bsub -V

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
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    Screenshot of the "Derivative" topic page
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    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
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    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
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    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
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