Professorship of the university of Cambridge by 
Ciro Santilli 37 Updated 2025-07-14 +Created 2025-06-17
Ciro Santilli 37 Updated 2025-07-14 +Created 2025-06-17This is a quick Microarchitectural benchmark to try and determine how many functional units our CPU has that can do an
inc instruction at the same time due to superscalar architecture.The generated programs do loops like:with different numbers of inc instructions.
loop:
inc %[i0];
inc %[i1];
inc %[i2];
...
inc %[i_n];
cmp %[max], %[i0];
jb loop;
c/inc_loop_asm_n.sh results for a few CPUs
. Quite clearly:and both have low instruction count effects that destroy performance, AMD at 3 and Intel at 3 and 5. TODO it would be cool to understand those better.
- AMD 7840U can run INC on 4 functional units
- Intel i7-7820HQ can run INC on 2 functional units
Data from multiple CPUs manually collated and plotted manually with ../c/inc_loop_asm_n_manual.sh.
Ubuntu 25.04 GCC 14.2 -O0 x86_64 produces a horrendous:To do about 1s on P14s we need 2.5 billion instructions:and:gives:
11c8: 48 83 45 f0 01 addq $0x1,-0x10(%rbp)
11cd: 48 8b 45 f0 mov -0x10(%rbp),%rax
11d1: 48 3b 45 e8 cmp -0x18(%rbp),%rax
11d5: 72 f1 jb 11c8 <main+0x7f>time ./inc_loop.out 2500000000time ./inc_loop.out 2500000000 1,052.22 msec task-clock # 0.998 CPUs utilized
23 context-switches # 21.858 /sec
12 cpu-migrations # 11.404 /sec
60 page-faults # 57.022 /sec
10,015,198,766 instructions # 2.08 insn per cycle
# 0.00 stalled cycles per insn
4,803,504,602 cycles # 4.565 GHz
20,705,659 stalled-cycles-frontend # 0.43% frontend cycles idle
2,503,079,267 branches # 2.379 G/sec
396,228 branch-misses # 0.02% of all branchesWith -O3 it manages to fully unroll the loop removing it entirely and producing:to is it smart enough to just return the return value from strtoll directly as is in
1078: e8 d3 ff ff ff call 1050 <strtoll@plt>
}
107d: 5a pop %rdx
107e: c3 retrax.
The Amino-acid Sequence in the Phenylalanyl Chain of Insulin by Ciro Santilli 37 Updated 2025-07-14 +Created 2025-06-17
Ciro Santilli 37 Updated 2025-07-14 +Created 2025-06-17This is where he started publishing the sequence of insulin. The paper gives the full B-chain sequence, which it tentatively calls the "Phenylalanyl Chain" because it starts with a Phenylalanyl.
The official link seems to be: portlandpress.com/biochemj/article/49/4/463/47212/The-amino-acid-sequence-in-the-phenylalanyl-chain It seems to explain the methods very well at first glance, with lots of schematics.
This is one of those things that when astronomers first saw them they went "oh fuck we've found extraterrestrial life".
Some examples:
Pinned article: ourbigbook/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.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact