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Mountain View To Partially Replace Google Wi-Fi

pchan- Re:ADD -- Billionaire Edition (69 comments)

As someone who lives in Mountain View, I'd like to second this post. Google WiFi has never worked well. In my experience it hardly ever worked at all. I'd be happy to be rid of it.

about a year ago
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US and Israel Test Missile As Syria War Tensions Rise

pchan- Re:International Dickwaving. (227 comments)

Uh, Syria was until quite recently one of our supporters in the region. We've had generally decent to good relations with the Assad regime. It cooled a bit since he started killing his people, but we tend to take a dim view of those who would kill their people because they started talkng democracy.

You might be confusing Syria with Jordan, because Syria was most definitely not our friend at any point. They have been a client state of the Soviet Union / Russia for many years, their Alawite (a form of Shia) minority runs the military dictatorship that is sponsored by Iran, and it props up Hizbollah in Lebanon. The US has had an arms and technology embargo on Syria since at least the 70's, there are no direct flights between the two countries, and there are no banking ties between them.

about a year ago
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Huffington: Trolls Uglier Than Ever, So We're Cutting Off Anonymous Commenting

pchan- Re:For a little tast of HuffPo hatefest (582 comments)

CNN's comments are equally terrible. It's hard to believe a reputable news organization allows them on its website.

about a year ago
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Watch a Lockheed Martin Laser Destroy a Missile In Flight

pchan- Re:Cool (177 comments)

Cost is not a big issue. The big issue is power.

A laser of this type is almost always a chemical laser because that is one of the best ways to portably produce that much energy in a hurry. The drawbacks of this are
1) the laser reactant supply needs to be reloaded after every shot or few shots. This is time consuming.
2) toxic chemical byproducts of the power-generating reaction. If you're defending a base in the middle of the desert, this may not be an issue. If you're defending land that you care about, like your home town, it is a big problem.

If the laser is battery-powered instead then prepare to wait a long time between firings for it to charge. Even a nuclear reactor on an aircraft carrier doesn't deliver the kind of wattage this needs in a burst, there will need to be a charge-discharge system.

Until the power problems are solved, don't expect to be seeing too many lasers shooting down missiles.

about a year and a half ago
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China's Allwinner Outsold Intel, Qualcomm In Tablet Processors In 2012

pchan- Re:So what? (121 comments)

Both are faster than fastest Tegra3.

For what definition of "faster than"? A7 is a pretty weak core. It was optimized for very low power and die area, not for high performance. Tegra3 uses Cortex-A9, which is an older design but actually faster if all else is held equal (same clock speed, equivalent memory subsystem).

(The reason you see quad A7 popping up in cheap Allwinner SoCs is that A7 is tiny. Really tiny. Area has a direct relationship with cost in semiconductor manufacturing. Also, ARM probably charges lower per-unit royalties for smaller / lower performance cores like the A7.)

Someone mod this guy up. A7 is a single issue, in-order core with basically no frills. An A9 like in the Tegra 3 is a triple issue out of order processor with a much faster FPU. It blows an A7 away in performance by a wide margin, although it is a much larger and more expensive chip.

about a year and a half ago
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China's Allwinner Outsold Intel, Qualcomm In Tablet Processors In 2012

pchan- Re:So what? (121 comments)

These are cheap for a reason, and they're unpopular in the rest of the world for a reason.

The Allwinner chips used in these tablets are all ARM Cortex-A8 based. A Cortex-A8 is basically unfit for a tablet. The lowest end tablets sold by Apple, Samsung, Motorola, Sony, Acer, and Asus 4 years ago didn't have a CPU this slow. Just because they can get away with selling these in China doesn't mean that they are worth anything.

about a year and a half ago
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Google Removing Ad-Blockers From Play

pchan- Re:"Don't Be Evil" My Arse (337 comments)

"Don't be evil" is the greatest marketing line in the history of technology because so many doe-eyed nerds wholeheartedly believed an advertising company has their best interests in mind.

about 2 years ago
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Intel Announces Clover Trail+ Atom Platform For Smartphones and Tablets

pchan- Re:What is the selling point, exactly? (56 comments)

Intel brings x86 compatibility. But that's no benefit on mobile, and will often be a slight liability.

It's actually a massive liability. I can boot an ARM Cortex-A9 in 1000 lines of assembly. An Atom requires a multi-megabyte binary blog delivered by Intel (source unavailable) to simple turn on an Atom. And yes, it does start out in 16-bit real mode as if anyone wants that. Can you guess which one of these is more debuggable?

And of course, the ARM architecture is offered by multiple makers, in all kinds of configurations of core types and numbers, clock speeds and so on. With Intel you get what one single company decides to offer, and that's it. Not directly relevant to us consumers of course, but it does mean it's more likely the ARM set-up in your phone or tablet is adapted specifically for that hardware, not a more generic one-size-fits-all spec.

Today Intel sells three versions of the same desktop chip; a high end one with all of the features enabled, a midrange one with some features disabled, and a low end one with most features disabled. Device makes know that once Intel is in a position of strength, they will do to mobile chips exactly what they are doing to desktop chips today. Let's look at one feature: SHA hashing engine. Intel Core i7 devices have this built in. Core i3 also has this but disables it. What if you want a low end SoC with a SHA engine? Any ARM vendor will sell you one, SHA engines are cheap and easy and everyone has one. Intel makes you pay for the high end part just to get a minor feature. Multiply this by all of the other SoC components and you'll see why nobody wants Intel to be in the lead. With ARM, chip vendors are competing on features, performance, and price. Nobody is picking ARM the company, they are picking the ARM ecosystem of chip designers and chip fabricators where everyone competes.

about 2 years ago
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The State of BSD At the Start of 2013

pchan- Re:OSX is doing great (91 comments)

It has a lot of BSD code in it and continues to share code with the other BSDs.

Really? I was under the impression that Apple do not distribute any source code for Darwin on ARM. Please show me where I can obtain the XNU ARM kernel source that is used in iOS.

Why would you need that? The platform-specific part of the kernel is a fairly minor part of the overall code. There's a lot more code investment in the VM, the FS, the network stack, and other major kernel subsystems, which are all generic code and distributed to the public, than the specific implementations of low level locks, interrupts, and page table map managers. The fact that we can't build and run XNU on ARM doesn't mean that we can't share code with it.

about 2 years ago
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The State of BSD At the Start of 2013

pchan- Re:OSX is doing great (91 comments)

iOS is doing even better.

There seem to be some uninformed posters here, so here is the OS X relationship to BSD:
The OS X/iOS kernel is based on Mach, which is a microkernel mashed together with a BSD kernel. It has a lot of BSD code in it and continues to share code with the other BSDs. It has features borrowed from BSD such as DTrace, PF firewall, file system support (including ZFS before it was removed), the networking subsystem, kqueue, jails, and others. While Mach is fundamentally different in some ways, to a POSIX binary it looks and feels just like any other BSD system.

The OS X userland is also based on BSD and was originally derived from FreeBSD. It uses the BSD libc and many of the command line tools are from the BSD world (from grep to ssh). It also includes some GNU tools, such as bash. Apple is actively working on replacing many of these, and they recently dropped GCC and GDB and replaced them with Clang and LLDB.

about 2 years ago
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Ask Slashdot: What Would It Take For Developers To Start Their Own Union?

pchan- Re:Large Libertarian Contingent (761 comments)

Oh god. Imagine if developer unions do happen and then I'd have to choose between working at a unionized company full of idiots or working at a non-union company that is staffed with Libertarians. I'd probably quit programming forever.

more than 2 years ago
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Department of Homeland Security Wants Nerds For a New "Cyber Reserve'"

pchan- Re:Sure, with some conditions... (204 comments)

It does sound like fun and I would enjoy it given the right working conditions, though I imagine these are highly unlikely to be found in a military operation.

However, no lawyer can get you the guarantee you're looking for. If you are a male and a United States citizen, you'll remember having registered for Selective Service ("The Draft") before your 18th birthday. Under the right conditions any registered person can be called up for service, all it takes is an act of Congress.

more than 2 years ago
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ARM Announces 64-Bit Cortex-A50 Architecture

pchan- Re:Time to learn.. (160 comments)

the ARMv8 back end for LLVM was written entirely by one guy in under a year and already performs well (although there's still room for optimisation).

Where can I find this LLVM back end? It does not appear to be on llvm.org.

more than 2 years ago
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ARM Announces 64-Bit Cortex-A50 Architecture

pchan- Re:Relaunch (160 comments)

In the first half of next year, there should be three almost totally independent[1] implementations of the ARMv8 architecture, with the Cortex A50 appearing later in the year.

Can you name the three vendors? Qualcomm for sure. Marvell seems likely. Nvidia says they will have a chip out, but I have serious doubts about their ability to deliver.

more than 2 years ago
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MIPS Technologies Porting Android 4.1 to MIPS Architecture

pchan- Re:Fragmentation (100 comments)

ARMv8 is not eliminating them, it's reducing the number of instructions that have them. Conditional instructions are useful because you can eliminate branches and so keep the pipeline full. For example, consider this contrived example:

if (a < b)
  a++;

On ARMv7 and earlier, this would be a conditional add. The pipeline would always be full, the add would always be executed, but the result would only be retired if the condition is true. On MIPS, it would be a branch (complete with the insanity known as branch delay slots, which if you look at the diassembly of most MIPS code typically means with a nop, so you get to waste some i-cache as well) and if it's mispredicted then you get a pipeline stall.

On ARMv8, you don't have a conditional add, but you do have a conditional register-register move and you have twice as many registers. The compiler would still issue the add instruction and then would do a conditional move to put it in the result register. From the compiler perspective, this means that you can lower PHI nodes from your SSA representation directly to conditional moves in a lot of cases.

Basically, 32-bit ARM is designed for assembly writers, ARMv8 is designed for compilers. As a compiler writer, it's hands-down the best ISA I've worked with, although I would prefer to write assembly by hand for ARMv7. I wouldn't want to do either with MIPS, although I currently am working on MIPS-based CPU with some extra extensions.

Actually, ARM's reasoning is that modern branch predictors on high end AP's can do a good enough job of following a test and branch and keeping the pipeline(s) full that there is very little value in conditional instructions on future chips. It's hard to cause a pipeline stall or bubble by branching a few instructions forward or back on these CPUs since they are decoding well in advance of the execution pipelines. Added to that, there is an energy cost in executing an instruction and throwing away the result. Obviously, not all cases are wins. In the example you noted, a register to register mov on a register-renaming system is basically a 0-cycle operation (never makes it out of the instruction decoder), so it's hard to do better than that.

more than 2 years ago
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MIPS Technologies Porting Android 4.1 to MIPS Architecture

pchan- Re:In case you're wondering (100 comments)

This is either either comedy or extreme stupidity, but I can't tell which.

more than 2 years ago
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Sprint CEO Defends Company's Decision To Bet It All On the iPhone

pchan- iPhone users (187 comments)

They are also more attractive and have great personalities

more than 2 years ago
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AP and 28 News Groups To Collect Fees From Aggregators

pchan- Re:slashdot (303 comments)

Slashdot is more of a duplicator than an aggregator.

more than 2 years ago
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Israeli Spyware Sold To Iran

pchan- Re:Iran never called for Israel's destruction (164 comments)

This is a reference to an older quote by Khomeini, but in Khomeini's days Iran was an ally of Israel. The alliance was broken off after the 1990 gulf war, because with Iraq gone and the USSR gone Israel had to change its strategy and Iran became a regional competitor.

I stopped reading after this sentence since it is so wrong, I assume the rest of it is also drivel. Israel and Iran were allies up until the Islamic revolution of 1979 in which Khomeini took power. You may have heard about the Iran hostage crisis, which happened at the same time when Iran's friendly relationship with the US was similarly dissolved. The Islamic council of Iran, which still rules today, has always been hostile to the US and Israel

more than 2 years ago
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Apple iOS 4.2 Hands-On

pchan- Re:"Other minor changes"? (212 comments)

This is a huge deal for developers since the iPad and iPhone/touch are now running the same software release. This means that developers no longer needs to target iOS 3.2 as the lowest common denominator for all devices, and can instead start using the new 4.x features (assuming they don't care about the very first generation iPhone/touch).

about 4 years ago

Submissions

pchan- hasn't submitted any stories.

Journals

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The Irony of the situation

pchan- pchan- writes  |  more than 9 years ago

I wasted my last mod point on the following post by an AC. I shall have to make use of it.

----------
ironic
Audio pronunciation of "ironic" ( P ) Pronunciation Key (-rnk) also ironical (-rn-kl)
adj.

            1. Characterized by or constituting irony.
            2. Given to the use of irony. See Synonyms at sarcastic.
            3. Poignantly contrary to what was expected or intended: madness, an ironic fate for such a clear thinker. ....

ironically adv.
ironicalness n.

                Usage Note: The words ironic, irony, and ironically are sometimes used of events and circumstances that might better be described as simply "coincidental" or "improbable," in that they suggest no particular lessons about human vanity or folly. Thus 78 percent of the Usage Panel rejects the use of ironically in the sentence

    In 1969 Susie moved from Ithaca to California where
    she met her husband-to-be, who, ironically, also came
    from upstate New York.

Some Panelists noted that this particular usage might be acceptable if Susie had in fact moved to California in order to find a husband, in which case the story could be taken as exemplifying the folly of supposing that we can know what fate has in store for us. By contrast, 73 percent accepted the sentence

    Ironically, even as the government was fulminating
    against American policy, American jeans and
    videocassettes were the hottest items in the stalls
    of the market.

where the incongruity can be seen as an example of human inconsistency.

irony Audio pronunciation of "irony" ( P ) Pronunciation Key (r-n, r-)
n. pl. ironies

1.
        1. The use of words to express something different from and often opposite to their literal meaning.
        2. An expression or utterance marked by a deliberate contrast between apparent and intended meaning.
        3. A literary style employing such contrasts for humorous or rhetorical effect. See Synonyms at wit1.
2.
        1. Incongruity between what might be expected and what actually occurs: "Hyde noted the irony of Ireland's copying the nation she most hated" (Richard Kain).
        2. An occurrence, result, or circumstance notable for such incongruity. See Usage Note at ironic.
        3. Dramatic irony.
        4. Socratic irony.

[French ironie, from Old French, from Latin rna, from Greek eirneia, feigned ignorance, from eirn, dissembler, probably from eirein, to say. See wer-5 in Indo-European Roots.]
[ Reply to This | Parent ]

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your spam-prevention idea won't work. here's why:

pchan- pchan- writes  |  more than 10 years ago

fill out in response to stupid spam ideas. not written by me, shamelessly stolen.

------------------------

Your post advocates a

( ) technical
( ) legislative
( ) market-based
( ) vigilante

approach to fighting spam. Your idea will not work. Here is why it won't work. (One or more of the following may apply to your particular idea, and it may have other flaws which used to vary from state to state before a bad federal law was passed.)

( ) Spammers can easily use it to harvest email addresses
( ) Mailing lists and other legitimate email uses would be affected
( ) No one will be able to find the guy or collect the money
( ) It is defenseless against brute force attacks
( ) It will stop spam for two weeks and then we'll be stuck with it
( ) Users of email will not put up with it
( ) Microsoft will not put up with it
( ) The police will not put up with it
( ) Requires too much cooperation from spammers
( ) Requires immediate total cooperation from everybody at once
( ) Many email users cannot afford to lose business or alienate potential employers
( ) Spammers don't care about invalid addresses in their lists
( ) Anyone could anonymously destroy anyone else's career or business

Specifically, your plan fails to account for

( ) Laws expressly prohibiting it
( ) Lack of centrally controlling authority for email
( ) Open relays in foreign countries
( ) Ease of searching tiny alphanumeric address space of all email addresses
( ) Asshats
( ) Jurisdictional problems
( ) Unpopularity of weird new taxes
( ) Public reluctance to accept weird new forms of money
( ) Huge existing software investment in SMTP
( ) Susceptibility of protocols other than SMTP to attack
( ) Willingness of users to install OS patches received by email
( ) Armies of worm riddled broadband-connected Windows boxes
( ) Eternal arms race involved in all filtering approaches
( ) Extreme profitability of spam
( ) Joe jobs and/or identity theft
( ) Technically illiterate politicians
( ) Extreme stupidity on the part of people who do business with spammers
( ) Dishonesty on the part of spammers themselves
( ) Bandwidth costs that are unaffected by client filtering
( ) Outlook

and the following philosophical objections may also apply:

( ) Ideas similar to yours are easy to come up with, yet none have ever
been shown practical
( ) Any scheme based on opt-out is unacceptable
( ) SMTP headers should not be the subject of legislation
( ) Blacklists suck
( ) Whitelists suck
( ) We should be able to talk about Viagra without being censored
( ) Countermeasures should not involve wire fraud or credit card fraud
( ) Countermeasures should not involve sabotage of public networks
( ) Countermeasures must work if phased in gradually
( ) Sending email should be free
( ) Why should we have to trust you and your servers?
( ) Incompatiblity with open source or open source licenses
( ) Feel-good measures do nothing to solve the problem
( ) Temporary/one-time email addresses are cumbersome
( ) I don't want the government reading my email
( ) Killing them that way is not slow and painful enough

Furthermore, this is what I think about you:

( ) Sorry dude, but I don't think it would work.
( ) This is a stupid idea, and you're a stupid person for suggesting it.
( ) Nice try, assh0le! I'm going to find out where you live and burn your
house down!

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