Previously discussed here: https://news.ycombinator.com/item?id=42156977
246 karma · joined December 29, 2021
[1] https://cis.temple.edu/~giorgio/cis307/readings/futex.pdf
Is this a fundamental limitation of iOS widgets/APIs, or just something WhatsApp hasn't implemented? Curious if others have found better ways to handle this on iPhone.
[1] https://www.tomsguide.com/how-to/how-to-use-the-WhatsApp-wid...
Recent versions of macOS restrict monitoring of the keyboard for security reasons. For that reason, one of the following must be true:
- The process must run as root.
- Your application must be whitelisted under "Enable access for assistive devices." Note that this might require packaging your application, since otherwise the entire Python installation must be whitelisted.
- On macOS versions after Mojave, you may also need to whitelist your terminal application if running your script from a terminal.
[1] https://pynput.readthedocs.io/en/stable/limitations.html#mac...
TLA+ isn't taught in most universities and while I've read about so many interesting applications, I'm yet to convince myself that someone would hire me for knowing it rather than just teaching it to me on the job. Any tips to get started would also be appreciated!
, is encoded as %2C
/ is encoded as %2F
[1] https://cpu.land
> "This is what I infer when I see someone who is comfortable in their unique strangeness, too. There probably exists someone who enabled that evolution of personality. A parent, a friend group, a spouse. It is rare for people to come into themselves if no one is excited and curious about their core, their potential. We need someone who gives us space to unfold."
[1] https://jvns.ca/blog/2024/02/16/popular-git-config-options/
I suspect everything after "This comprehensive analysis offers insights..." is written with the help of an LLM too.
In an SSD, a write operation can only be done when the page is already erased. However, the unit of read/write operations are a page, while the unit of erase operation is a block. That means for a disk write, a naive implementation needs to read the whole block, erase the block, then write updated data back to the block, which is unacceptable. Furthermore, blocks should wear out uniformly, otherwise, the SSD would lose capacity.
To tackle these problems, SSD introduces Flash Translation Layer (FTL) which helps to build an illusion of random access device. To achieve this, FTL employs an approach very similar to LSM trees. Writes are always written to new, already erased pages, while in the background, garbage collects (GC) outdated data. FTL needs to keep a map from the user’s logical address to physical address on SSD, both in-memory and persistently.
So to answer your question, why are sequential writes are faster than random writes on SSDs? Because the address map table is smaller since new data is consecutive in larger chunks. Garbage Collection is simpler and only metadata needs to be updated. Erasing a block is required anyway.