398 karma · joined March 25, 2021
This is incorrect, TUM has a PET scanner (site in German): https://nuklearmedizin.mri.tum.de/de/Patienten-Zuweiser/Pet-... Can't comment regarding the other observations.
By the way, NMI still exist on x86 to this day, but AFAIK they're only used for serious machine-level issues and watchdog timeouts.
In other words, I wouldn't expect a improvement in capturing actual 48MP pictures in phone cameras, apart perhaps from pixel binning to a smaller size and similar techniques.
Disclaimer: I haven't followed camera tech very closely recently, and I'm not an expert. Take my opinion with a grain of salt.
The workflow you'd like already exists one to one in Isabelle: You can simply type "nitpick" halfway through a proof and it will try to generate a counterexample in that exact context.
Disclaimer: Not a native speaker, I hope I got the annoying structure of those "what to look for when buying X" blog articles right...
To continue your line of thinking, when we add salt and pepper to a dish we've cooked, are we really doing it because we have a developed a thorough understanding of the human olfactory and gustatory systems [1] system, or because it tasted good previously when applied to similar recipes?
And when it comes to understanding basic math, perhaps the patterns are still a tad to complicated for LLMs. Maybe there are too many surprising rules that appear out of nowhere and break the learnt patterns. But children struggle with those rules as well when they first come across them. Think about division through zero - when coming across the rule for the first time, you might wonder why it exists, instead of e.g. defining the result to be infinity. The answer to that question (not just "because that's the way things work!") is not obvious at all, to be honest I wouldn't be confident enough to attempt giving an explanation here.
[1] I have to admit I had to look gustatory system up: it's the biological term for the system behind the sense of taste.
In short, a Deref impl for some type T signals that T represents some level of indirection, and following/dereferencing that indirection can always be done in an unsurprising and trivial manner.
Git life pro tip (that you didn't know you needed until now): You can use .git/info/exclude (present in every Git repository) as a local, private version of .gitignore. It has the same syntax as .gitignore, but isn't tracked by Git. So you could add .cargo/config.toml to .git/info/exclude, changing the linker locally without Git considering it as an untracked file. I generally use this feature to ignore files that are specific to my development setup which I don't want to list in .gitignore.
With this in mind, I'm baffled about how many products with non-stick surfaces are marketed as safe up to 240C, considering that household ovens are often bad at controlling temperatures and can swing 20-30C above and below the set temperature.
This is why some common locking advice does not really apply to kernel code. Another example would be "avoid using spinlocks, prefer a mutex" - spinlocks are widely used in the kernel since they're the most straightforward alternative to mutexes.
Not disagreeing with the parent post, just wanted to add some context why LWN likes to talk about lockless algorithms.
[1] Actually, the kernel differentiates between hardirqs and softirqs, but that's not important here.
On the other hand, I find it's easy to be downvoted into oblivion for no apparent reason. I find it hard to just ignore and forget about those threads, even though I know I should. Example (sorry, I have to get this off my chest): a redditor with a history of substance abuse started with winemaking (as a hobby) and asked how many glasses of wine they could safely consume. A physician (verified in that subreddit) responded that two glasses every day would be fine. I commented (as a medical layperson) that suggesting OP that it's safe to drink two glasses of wine every day (not just every now and then) might not be a good idea considering their history, at least to my knowledge. Suffice to say, that day I learned that some people seem to be easily offended when commenting about reasonable alcohol consumption considering past addictions. Or perhaps I'm vastly overestimating the risks of substance abuse disorders...
[1] https://stackoverflow.com/questions/38304877/why-stdhashint-...
[1] Actually systemd-oomd to be precise, but let's not start the userspace OOM killer debate again in here
I'd say that the color primarily serves as a visual aid that does not depend on passengers understanding the local language or remembering the name/number of the line. And color serves an important role in interchange stations, where it aids navigation by providing visual cues where you should go.
A nice example of this is the London Underground, where visual cues using the line color are used extensively. In Green Park, there is a mosaic on the walls between the grey Jubilee line and the blue Piccadilly line. The tile pattern smoothly changes between grey on the Jubilee side and blue on the Piccadilly side. If you look at a Tube map, the line colors are all sufficiently distinct so that you're never confused which line is which in busy parts of the map.
On the other hand, IMO a negative example of line colors would be the Berlin S-Bahn. Have a look at the map [1] and tell me whether you have an easy time differentiating S41/S41/S45/S47 as well as S3/S5/S7/S9 (as well as U2/U7/U8). They all use extremely similar colors. If you're new to the system, you can't just remember to use the "blue line", as there Alexanderplatz, Friedrichstraße and Charlottenburg each have three "blue lines".
[1] PDF can be downloaded at https://www.vbb.de/en/driving-information/maps/ - select "S+U-Bahn in Berlin - suburban trains and underground"
At least for me it's perfectly understandable (except the "Mrs" part). This reminds of those "did you know you can flip characters randomly and our brain can still understand the text" copypastas that can be found everywhere. I think it's probably quite similar for word order: As long as your sentence structure is not extremely complicated, you can probably get away with changing it any way you like. Just like nobody has issues understanding Yoda in Star Wars.
Although I think there are some limits to changing word order - I can imagine complicated legal documents might get impossible to decipher if you start randomizing word order.
[1] My goal is to implement realistic train track geometries, including transition curves, using Euler spirals or perhaps a simpler curve.
[2] For example, I'd like to try tessellating curves via shaders as required, based on zoom level etc.
Generally speaking, just because modern x86 CPUs use numerous abstractions for high-level instruction set features does not mean they don't use cycles. (Clock) cycles are an inherent feature of synchronous logic, and all CPUs (modern as well as ancient) use synchronous logic. Yes, there might be some esoteric outliers, but 99.9% is synchronous.
The difference to ancient CPUs is that modern CPUs don't necessarily retire (essentially, "execute") an instruction in every clock cycle. In any given clock cycle, a CPU might retire none, just one or even multiple instructions.
A typical application (where clock cycles are important) is looking at the number of retired instructions per cycle (IPC), which can give a rough overview of whether a program is frontend-bound or backend-bound. You can try this yourself using "perf stat" (part of the Linux perf tools): Try running different applications using perf stat and look for "insn per cycle" in the report. You will generally find that interpreted programs (Python, Node etc.) will have a mediocre IPC of well below 1 (due to poor cache utilization and branch mispredictions) while compiled, optimized programs might reach an IPC of 2. A high IPC value is not necessarily better though, it's complicated^TM.