> The best way is always to stop when you are going good and when you know what will happen next. If you do that every day when you are writing a novel, you will never be stuck.
This is always hard. When things are going well (in flow, on a roll etc.) you want to continue and get it all out. When you get stuck in writing, programming or anything, taking a break seems to make sense after a few moments of toil.
Yes and besides things happen during the next day, that doesn't mean you'll want to get going again, regardless of how good of a state you left progress in.
Maybe it’s like anything else... to get into an activity you have to get some quick wins scaffolding. So you set it up from your previous day but not something insurmountable. But the same could be true if you were just starting on a new problem. A large reward/effort ratio motivates you to see what else you can get. And that’s true regardless of whether you were the one who set up the problem the day before.
In traditional I/O, a hardware interrupt is triggered whenever data arrives at hardware boundary and the interrupt can get serviced by any core that is available to the scheduler. One can imagine how much overhead is involved in context switching whatever that core was doing before, setting up the registers, moving data and then relinquishing the core back to OS - in this model, dedicated cores serve I/O in a memory mapped ring buffer like data structure sized to your application needs. There is no allocation/deallocation overhead, no management beyond moving a pointer and no context switching. If you can spare the cores, this can significantly improve performance.
In one use-case, I was able to quadruple the performance on a 32 core xeon by installing 4 10gbps ethernet cards and dedicating the first eight cores to I/O (2 per interface). This is all about latency but with proper care, it also improves throughput.
Someone more familiar with kernel workings than me should clarify, but my understanding is that IO generally happens via a syscall which requires the thread/process in question to context switch between userspace and kernel space, which can be very expensive. By enabling IO polling in userspace, you get to avoid that context switching.
The motivating benefit is performance, but a side one the author mentioned on Twitter https://twitter.com/axboe/status/1073320502532263936 is sidestepping Meltdown and similar vulnerabilities from having the kernel and the OS in the same address space (even though they're separated by a privilege boundary). In a scheme like this, you can theoretically dedicate one core to the application and a separate one to the kernel, and minimize speculation, cache sharing, etc. between the two. The application and the kernel share a portion of memory, so the kernel doesn't ever run on the application's CPU.
This is questionably practical for a general-purpose machine, but for a server system used entirely as a hypervisor, or web server, or file aerver, or something, it might fit really well.
Depends on the use case; keep in mind that syscalls are slow, too. If you have an application that does significant computation on lots of data (think a scientific calculation/simulation), having another core on the same socket read ahead from disk to RAM might be much more efficient than pausing computation to read synchronously. Or if you're a file server that is just passing things back to the kernel's network layer, you might not even need to see the contents of RAM yourself.
Performance, latency variability and sanity. It’s somewhat easier to write applications without having to make a syscall, which may have unknown latency (even if it’s a non blocking poll).
The official version is that Telegram was used by terrorists who blew up the metro in Saint Petersburg.
The real reason is more simple: it's mostly used by the small middle class, people working in tech and business. The current laws in Russia were used to block LinkedIn, but they didn't touch Facebook or Twitter — that would be too much.
It could be, but much more people use WhatsApp in Russia, people like my parents who haven't noticed any laws against the free internet before.
They don't touch Signal or anything else as well.
WhatsApp has lots of clients for the shitty phones poor people use and a ton of Russians use WhatsApp. It's also possible that some implementations of these WhatsApp apps or the phones that host them are hacked, while others are not so it could be less of a binary distinction than one might assume.
Generally, I try to avoid criticising others but this logic is really disturbing and dangerous and I am very worried about people who stand behind it. It hasn't gotten us anywhere. It never will.
None of the above. What the parent comment is sarcastic about is a line of argument people use, especially politicians who want to promote their agendas.
Terrorists do use the air to convey voice; air is their primary communication medium for propagating their terrible ideas, and arranging their despicable plans. If we denied them access to air, to stop their voice communication, it would severely limit their ability to harm us. Isn't saving even just one child's life worth it?
And don't worry about the terrorists without air not being able to talk about the legal, daily matters. Relevant institutions are already equipped to handle deaf and mute people. They could also just use internet or other service.
Just deny them air so they can't talk, okay? It's the common sense solution. /s
Slippery slope is a thing, especially when actors with under-handed intentions ask for simplistic, ham-fisted solutions. Once a precedent is established for censorship or snooping, it's pretty hard to draw, and defend, a line in the sand.
Does this mean that we should sit back and enjoy the show because "actors with under-handed intentions" and "precedent"s? Wake up. We can only get through collectively.
There is no corporate entity supplying terrorists with air. This is why this consumer-based end-to-end encrypted chat messenger space isn't going to go anywhere. Telegram is delusional if they think nations will let them operate this kind of a business. Every terrorist attack where Telegram is used will paint a bigger and bigger bullseye on their backs. The media will get in on it. The public will get in on it. Lawmakers will get in on it. Hacker News will get in on it.
The witch hunt against Facebook shows how this will look though the particulars will be different. At the end of the day, Telegram has devs that need to eat and servers to pay for and at the very least all revenue sources will be denied to them.
> Every terrorist attack where Telegram is used will paint a bigger and bigger bullseye on their backs. The media will get in on it. The public will get in on it. Lawmakers will get in on it. Hacker News will get in on it.
Here I was, thinking that we here at HN aimed higher.
> The witch hunt against Facebook shows how this will look though the particulars will be different.
Witch hunt usually implies baseless, made up accusations.
When it comes to Facebook I'd phrase it differently; maybe something about consequences or justice?
This in amny ways is analogous to the gun debate in the United States. Everytime there is a major shooting, there are calls for certain types of guns to be banned. Every time there is a terrorist attack coordinated by an encrypted chat app, there will be calls to wither ban it or have a backdoor.
The parent post is a nice example of the type of underhanded rhetoric that will eventually be used to sway the public in favor of banning encryption.
Pretend your target is inherently evil, and can only be used for inherently evil things. (Terrorism! Child abuse! Piracy!) Then you're perfectly set up to vilify anyone who dares to question your position.
Telegram is widely popular among that part of the country who like doing illegal things; it was even endorsed by local darknet, they set up bots to help circumvent blocking and stuff like that. Really juicy target for banhammer compared to whatsapp that has a smaller and more legitimate user base (in russia).
Yes, I would like to know how that works since whatsapp is constantly being advertised as super secure because of using the signal protocol. Do Russians get a different version of the app?
Assuming they set up signal protocol correctly, which I'm sure they did since Open Whisper Systems partnered with WA to set it up right, they're likely just sharing details on users' contact lists.
Considering Facebook owns WhatsApp this isn't surprising, they're definitely happy to share this information (ever seen someone in your FB "suggested friends" list after messaging them on WA?)
If they had pushed a different version of the app to Russia or there was a way of breaking message encryption I'm sure someone would have noticed by now.
I think you can pretty easily guess from the #deletefacebook statement of the whatsapp founder that they did not implement the protocol "correctly".
Corporate statements about the security and privacy of their products usually leave open the possibility that they engage in lawful intercept. Even if they don't they can always just lie and use the fact that they have national security letters barring disclosure as legal cover if it ever comes out.
They could probably still use this "design feature" (that Signal doesn't have) to hack users who don't authenticate the people they're talking with (also authentication isn't enabled by default on WhatsApp, but it is on Signal):
If you're a user of WhatsApp, make sure you enable the two-factor authentication PIN, too, because otherwise it should be relatively trivial for your own government to gain access to your account by using your number with the local carrier's help (it's also possible to do it without the carrier's help, given how broken the security of carrier networks is). Many Telegram users were hacked this way by the government in Russia, too.
Whatsapp makes a local backup in internal storage everyday. There is no setting to disable this backup. There are many opportunities to access the chat history, specially for Facebook, that wouldn't require cheating with the signal protocol.
There is a formal process for that. First, a messenger must register with Roskomnadzor (a government organization). So if a messenger is not on the list, it doesn't have to share anything yet.
What i think about it: why not build in ToR client right into the app itself, make it update itself, then always use ToR with obfs4, and openly declare that there will be no compliance, and you can't do anything?
Only concern could be the file size, but Orbot is only 12MB for example.
It will also greatly increase popularity of the messenger.
Cause for them to use it overseas it needs to be unblocked internally (to Russia)? Russia can always "whitelist" some applications for government officials too. Or y'know not rely on third-parties and roll their own solution, not like Signal's protocol isn't open sourced.
I don't understand the point you're trying to make.
Blocking Telegram helps Russian intelligence operations by making it appear like as if the Russian government did not have access to the vast majority of conversations over Telegram.
"Blacklist all by default, whitelist as needed" is how we build most secure systems right? I'll admit it feels strange applying that construct to day to day browsing.
I have started using a "Quick Javascript Switcher" extension some years ago to easily opt-in for certain pages but have js disabled by default.
This was one of the best quality of life decision in terms of web browsing I have ever made.
The vast majority of pages that I randomly access (e.g. from hacker news) are text based and usually work just fine without js. But the time until I can start reading is much faster (less jumping around of content) and I don't get the growth hackers modals shoven down my throat two paragraphs in. The pages I use regularly are usually white listed
More like "disabled by default," actually. It's mostly ads/tracking, popovers, and other annoyances, and it's easy to selectively turn it back on where you really need it. This approach isn't for the general public yet.
No page shows JavaScript for me until I enable it with NoScript. It's too sad that Firefox Focus on Android doesn't allow plugins or disabling JS, it make it makes the whole thing pointless.
Yeah but OP is trying to point out a specific piece of information that's relevant for hacker news users. It wouldn't have been read through otherwise.
I'm really happy to see PostgreSQL doing so well. They've been up against MySQL and Oracle for so long and really deserve it due to all the hard work the team have put into the amazing OSS project.
As far as I'm concerned, PostgreSQL should be the standard for any new free software projects. It's just too bad so many older projects (Wordpress, etc.) are tied to MySQL.
