Hacker News new | past | comments | ask | show | jobs | submit | uvdn7's comments login

Love it! I wonder if the team knew this explicitly or intuitively when they deployed the strategy.

> We created a rule in our central monitoring and alerting system to randomly kill a few instances every 15 minutes. Every killed instance would be replaced with a healthy, fresh one.

It doesn't look like they worked out the numbers ahead of the time.


I was thinking the same. There are many mutexes out there, some are better at certain workloads than the rest. DistributedMutex and SharedMutex come to mind (https://github.com/facebook/folly/blob/main/folly/synchroniz..., https://github.com/facebook/folly/blob/main/folly/SharedMute...) Just like hashmaps, it's rarely the case that a single hashmap is better under _all_ possible workloads.


Yeah.

I should say, though, that if you're on Windows then I have yet to find a real workload where SRWLock isn't the fastest (provided you're fine with no recursion and with a lock that is word-sized). That lock has made some kind of deal with the devil AFAICT.


The downside of the deal with the devil...

https://old.reddit.com/r/cpp/comments/1b55686/maybe_possible...


That was a fun rabbit hole to go down.


Math, sure - doesn't the understanding of physics also go through changes? Do we really understand the reality of the world; or how do we know our current understanding of it won't change?


Asimov wrote an essay called "relativity of wrong" that I think does a good job of capturing the changes our understanding of the world goes through.

Yes, Einstein's theory of relativity was a change from Newtonian physics but it's a fairly minor correction for most practical purposes and Newtonian physics is still important to know and understand.

So yeah, our understanding of physics will likely change but it'll only matter in more and more extreme edge cases and will likely build on our current understanding. Maybe it'll result in us finally having fusion reactor, room temperature super conductors, or quantum computers but you're still going to get a roughly parabolic arc when you throw a ball through the air.


I think 20 years for physics won’t really make much of an impact. Maybe you build an even bigger particle accelerator and confirm another well accepted idea. But, there’s not really going to be groundbreaking changes that affects people on the daily.


The same happens in work place as well, when multiple people have similar ideas and it is unclear or impossible to credit who came up with the idea first. It is often the case that people with shared context had similar ideas independently when facing the same set of problems.

I have the impression that it is controversial about who invented the hybrid logical clock first as well. Although most people cite the Kulkani paper from 2015 I think?

Do people know who else claims to invent HLC first?


In the work place a manager will heroically claim credit.


If that happens, raise it his boss. If that doesn't work and you feel like vomiting on your mgr's face, do it. Don't hold back.


The biggest difference between automatically keeping an MV up to date vs keeping indices up to date is that the write amplification of the latter is a function of the index count you have, while the former is a function of data and query. It’s easy to come up with cases when users update a single db row, and you end up having to update millions of rows in a MV (eg the every row in the MV has a name “Rob” and Bob changes his name).

I read the timely dataflow which underpins materialize.com. It seems like we don’t necessarily need the support of loops, which timely dataflow allows, for regular SQL, which is a DAG of operators. It appears that as long as the database supports snapshot reads, one can have a push-based query execution to enable incremental MV updates. The problem, I think, is still in the write-amp-as-a-function-of-data, which is unbounded. It is very cool regardless.

The technique can be used for cache invalidation as well, given the data cached needs to be described in SQL, which seems reasonable.


Apple claims that its Weather App has integrated DS’s features. However, for a few times it’s ridiculously wrong. It said it’s cloudy when it’s raining onto the very phone, which I don’t remember happened to DS. Forecast for the next hour feels like as accurate as forecast for next month. I live in New England. I am going to miss DS a lot.


Please use the "Report an Issue" link at the bottom of the weather page to train their model or at least notify them that the assessment is wrong.


I think it boils down to cost. Digital content is extremely cheap to replicate and distribute; hence the quality of the content is assumed to be lower (and it’s usually the case). One doesn’t have to put in too much effort in producing digital content.

Now with ChatGPT, it’s even more so than ever. It’s practically free to produce digital content.

On the other hand, even by just printing out a doc increases the cost of replication and distribution significantly (compared to pure digital replication); hence the quality of the content is assumed to be higher.


Yes, and I think that's driven a novelty factor. If you spend all day on screens, it's the last thing you want to do more of. The paper book or vinyl record is special because it's disconnected and tactile.

I'm also gradually hearing friends come to realize that their ebooks and streaming movies may vanish at the whims of corporate licensing agreements, but their libraries of physical books and DVDs are durable.

Give it two more years and we might see letter-writing clubs emerge.


Rust borrows c++’s modern memory model verbatim.

C++ is a language that keeps innovating besides many legit reasons to hate the language. Having more competition is good. I would expect more rust/{your favorite language} concepts to show up in future versions of c++ (once proven to be a good idea in most cases).


By this reasoning, shouldn't Tesla pay users instead to enable FSD and collect data for them?


It seems they're doing quite well on their financials by offering access to FSD as a subscription. The misconception here is that FSD is needed for them to collect data - they collect autopilot sensor data on all cars regardless of FSD or not.


A tangent to that thought... "do you want people to be financially incentivized to get into novel situations to test situations where FSD was lacking data?"

I recall Waze had some point system to help gather positioning / speed data for side roads that it would try to have you go get with icons... and those were just fake internet points.


And no abstraction is perfect, as by definition an abstraction hides some details from the layer beneath. A good abstraction is one that allows you to not look under the hood most of the time. One can be happily writing code in their favorite programming language until you want better performance and started looking into cpu caches, branch prediction, etc. which are "breaks" the nice abstractions provided by the OS and high level programming languages.


Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: