Hypoxia and hyperventilatiion

Surfing https://news.ycombinator.com/item?id=43724523

Oxygen mask https://news.ycombinator.com/item?id=43723317 https://news.ycombinator.com/item?id=43723706

As a pilot, it was eye opening to see first-hand what happens to me when experiencing hypoxia. The trainers were talking to me, and I was replying, but was unable to tell them what 17 minus 4.5 was.

Hn: https://news.ycombinator.com/item?id=43695093

April 18, 2025

Packing fraction of globular protein cores is always close to 55%

The researchers, led by Corey O’Hern, developed computational models for all globular proteins in the Protein Data Bank, an online database, and measured their interior core regions to determine how densely packed they were. Every protein had a core packing fraction of 55%. That is, 55% of the space was occupied by atoms. That led the research team to two questions.

https://phys.org/news/2025-03-protein-mystery-core-fractions.html

April 16, 2025

memory consumption when using imap_unordered in Python multiprocessing

A separate thread is spawned to ingest data into the pool, but it doesn’t stop to wait until the tasks are processed. Therefore, if task definitions consume substantial amount of memory it can lead to OOM kill.

If you’re using multiprocessing.Pool, consider upgrading to concurrent.futures.process.ProcessPoolExecutor, because it handles killed workers better. It doesn’t affect the problem described in this question.

https://stackoverflow.com/questions/40922526/memory-usage-steadily-growing-for-multiprocessing-pool-imap-unordered

April 6, 2025

CST timezone

a quiz question would be to expand the abbreviation.

list of timezone names: https://www.timeanddate.com/time/zones/

February 6, 2025

Docker pulls entire image even if some layers were delivered with save/load

When saving an image from the graph-driver store, a new archive is created containing the uncompressed layers; saving/loading will produce the same layers as were pulled, but the save/load won’t include information about their compressed digests, because this information cannot be verified without the actual compressed artifacts (as pulled from the registry). Reconstructing the compressed layers is not possible due to compression algorithms not being 100% reproducible (they may be most of the time, but various factors, including CPU load, and CPU optimizations during compression can cause their checksum to differ).

https://github.com/moby/moby/issues/46664

January 23, 2025

"Amen" cadence

Cadence is the core tension in music theory. The most common one is called the authentic cadence - between V and I degrees of the scale. In blues however the cadence of IV to I is more typical.

Fun part is that IV to I is also called “Amen” candence, for its frequent use for “Amen” in hymns.

https://en.wikipedia.org/wiki/Cadence#Plagal_cadence

December 14, 2024

Brief comparison of Google Drive and Dropbox

Price per 2TB

  • GDrive $137.75 / year
  • Dropbox $120 / year

Privacy

When I shared a file with someone, and then want to: unshare and share with someone else.

Can the sharing link be reset for a particular file / folder?

NOTE on Dropbox:

You can only delete shared links that you create. If you invite someone to a file or folder with editing access, they can create their own link to share with someone else. You can’t manage those shared links

October 20, 2024

Software development is not a rocket science, or is it?

ref: https://toot.cat/@plexus/112403882840794498

May 9, 2024

VPN considered insecure

https://arstechnica.com/security/2024/05/novel-attack-against-virtually-all-vpn-apps-neuters-their-entire-purpose/

general practice for VPN, is to prioritize itself via defining more specific routing rules, which take priority over the default gateway. the attacker, however, can spin up another DHCP server, and use rule 121 to push some new routes to the client. Importantly, if the routes are more specific than the ones defined by the VPN, they will take over, and unencrypted traffic directed to the VPN interface will end up on the attacker’s machine.

the golden standard to avoid this vulnerability is using network namespaces: https://www.wireguard.com/netns/#the-new-namespace-solution

discussion: HN1 , HN2

May 7, 2024

Embouchures

The word embouchure originates from the French bouche - mouth. One of its meanings describes the mouth-work musicians do to extract sounds from brass musical instruments. More popularly, embouchures are those soft parts of the headphones that usually wear out too quickly :)

You are welcome, now you can’t unsee the link between headphones and lips wrapping a musical instrument!

May 2, 2024