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Comment Re:Answer me this... apk (Score 5, Informative) 44 44

The answer is that it varies - GPUs are anywhere from mediocre to useless at "normal" crypto.

It depends on whether the particular encryption algorithm/mode in use is parallelizable or not. For example, CBC is not parallelizable - you have to encrypt each block of data serially. GPUs are useless at CBC mode encryption. More modern modes like GCM and XTS are parallelizable to an extent, as you can encrypt multiple blocks at once, but there is still a serial dependency in the process (there is no real way of completely getting rid of all dependencies while keeping the algorithm usefully secure), so you still need to do some pre or post-processing of the data in a serial fashion. And even then, you're limited by bandwidth in/out of the GPU.

Public-key crypto (RSA, DSA, and ECDSA) isn't really parallelizable either as it only deals with small data sizes. And typical hash algorithms like SHA-1 and SHA-256 are also not parallelizable in their construction.

Thing is, CPUs these days have hardware AES encryption acceleration, making this mostly a moot point. GPUs are good at doing the same thing many times in parallel, which is what breaking encryption requires, but not regular usage.

Comment Lies, damn lines, and statistics (Score 1) 102 102

That one billion figure doesn't sound as impressive after one considers that it's fairly likely that it's mostly obtained by counting every Android install that comes bundled with Chrome. I'd be shocked, just shocked, if Google does NOT count someone who used Chrome a few times, before installing Firefox mobile. Like me, for example. I hardly ever use Chrome on my Googlephone. But, I'm sure I'm counted in that billion-plus figure.

Comment RTFA (Score 5, Informative) 227 227

The norecruitingspam guy himself spammed news.admin.net-abuse.email a few days ago with this. All he's offering is an email filtering service that blacklists the Jobdiva spambags.

He posted his screed in a Usenet thread that I started over five years ago, that's archived by Google, at apparently has a pretty high ranking when someone is searching for more information about all the spam they're getting from the Jobdiva spam factory. Over five years ago I happen to notice that every recruiter spam that I received turns out to have come from the Jobdiva spam factory. Ever since then, once or twice a year someone finds that thread in Google Groups, and post a "me too" to the Usenet group. Which I find pretty funny.

After figuring out where all my recruiter spam is coming from, it was a simple matter of adjusting a few settings on my mail server, and, poof!, it was all gone. Originally I never thought much of it, and only posted the first message in that thread as a means of sharing my thoughts, and nothing more, but apparently someone else now discovered effective email filtering and thinks it's the greatest thing since sliced bread. As Benny Hill would've said: biiiiiiiiiiiiiiiiig.... deal.

One good thing here is that now that he's got a good link from Slashdot, and, presuming that his web site is still up (haven't checked), because all his web site now only contains a big rant against the Jobdiva sleazebags, this will shine a bit of a brighter spotlight on those vermin, and perhaps shine some well-deserved sunshine on these sleazebags. Sunlight is the best disinfectant.

Comment Re:Wireless Networking (Score 1) 484 484

That's strange. My WNDR3700v3 is rock stable. The only time it goes down is when I lose power, once or twice a year. The router Is always busy. Various members of in my household are constantly streaming videos. I've got laptops, i-device, and android devices pinging the intertubes constantly. Everything works. I don't use "device discovery", whatever that is, though.

Comment Ugh, "Lolani'? (Score 2) 71 71

Oh geeeee..... The only good thing about "Lolani" is that it is a perfect remake of a classically terrible, awful, ST:TOS episode. It's a perfect homage to "Spock's Brain", and "Savage Curtain".

So from that viewpoint, it's a great episode. And I really enjoyed watching it, but only for its artistic value of a faithful recreation of a botched ST:TOS time filler. Really, I'll take "Fairest Of Them All", or even "Pilgrim of Eternity", over "Lolani", any time. And I do appreciate seeing The Incredible Hulk himself, in full-body green makeup; but it can't make up for the awfulness of the rest of the episode.

Comment Re:meanwhile... (Score 1) 755 755

Please read on what POSIX is first. It is what guarantees that your software will be portable, which is a foundation upon which UNIX is built.

Yes, POSIX is important. But as with any standard it defines the least common denominator. Couple that with the fact that POSIX was not updated in years and you have to address the least common denominator from more that 5 years ago (I think even longer...). That is an eternity in IT. A standard is fine, but it should not stop you from playing to your strength.

Systemd argues that an init system is closely related to the Kernel and should make all the fancy kernel features available to user space. There is enough precedence for this in commercial unix variants by the way: Many come with init systems tailored to their specific strength of their kernels. I do not see that as a bad thing. So far I am not aware of anybody in the BSD camp even wanting to port systemd. At least the FreeBSD developers said they wanted a modern init system, too, but they are going for something that plays to the strength of their own kernel. So why should systemd bother about being portable to OSes that want to come up with their own solution?

That BSDs require some compatibility layer is nothing new, either. There is support for Linux style /proc and IIRC even /sys in some of the BSDs! DBus, polkit and whatnot were ported over to the BSDs, too. So how is systemd any different than those projects? You will need to implement a couple of DBus interfaces and make sure those will do the right thing. Nothing new, nothing special.

There are projects on the BSDs as well, that are non-portable: LibreSSL and openSSH from openBSD spring to mind here. Those use interfaces from the BSD kernel. There a separate porting projects that bring those code bases over to Linux. They actually introduced a new kernel API due to libreSSL into the Linux kernel.

I see nothing bad in targetting specific platforms whatsoever. Yes, I do think POSIX is important: If you can do something with POSIX, then use that. If not, then use something else. And when in doubt target one platform and let people that care for other platforms port the stuff if they care.

Comment Re:Maybe not the power supply? (Score 1) 192 192

Usually, "epoxy" around the edges of a BGA chip is neither an anti-hacking attempt nor a light-proofing attempt. It's called underfill, and its chief purpose is to increase mechanical strength and make the bond more durable than tiny bare solder balls would be on their own.

Comment Re:Still ARM11, still a crappy CPU (Score 1) 355 355

Yes they are. Most multimedia processing is parallelizable, and thus benefits greatly from SIMD instructions - for example, just about every CPU-based video codec ever. If you want an actual example, I wrote a high-performance edge detection algorithm for laser tracing, with its convolution cores written in optimized in SSE2 assembly, and am hoping to write a NEON version. It'll never run reasonably on the original Raspberry Pi because it's too underpowered to do it without SIMD (I didn't even bother writing a plain C version of the cores, because honestly any platforms without SSE2 or NEON are going to be too slow to use anyway).

Obviously you can use SIMD instructions for a lot more, but multimedia is the obvious example. And as I mentioned, the Pi makes up for it for standard codecs only with its GPU blob decoder, but that doesn't help you with anything that isn't video decoding (e.g. filtering).

Comment Re: a billion operat per second enough for cat wat (Score 1) 355 355

ESP8266 only became a "thing" last year, so the community is still growing. But the manufacturer is cooperating and is releasing open SDKs, and the hobbyist community is enthusiastic about it. I personally intend to use a bunch of them to automate things around my apartment, so I guess I'll find out just how good/bad it is.

That's for developing on the ESP8266 core itself - if you just want to use the default firmware, plug it into your existing microcontroller platform (e.g. Arduino) and you get wireless connectivity and a TCP/IP stack (running on the module) with some trivial AT commands. Not as cheap since you're still using a separate core as the main app host, but still a really cheap way to add WiFi to something.

How can you do 'New Math' problems with an 'Old Math' mind? -- Charles Schulz

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