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Comment: Re:Last time one was used? (Score 2) 50

by gman003 (#49625943) Attached to: SpaceX Testing Passenger Escape System Tomorrow

SpaceX is getting some of the benefits of skipping the LAS, by using the same system for at least two tasks.

The primary use is as a propulsive landing system. That's probably the main way they'll be used. There's a backup parachute system, but they want powered landings to be the norm.

The secondary use is as an abort engine. It'll probably be rarely used, and I think it uses up all the fuel so an aborted launch will have to use parachutes, which will make for rougher landings but still plenty survivable. This way, they won't be carrying fuel that isn't used in some way during the flight.

A third possible use is as an in-flight maneuvering system. This is mostly done using the smaller Draco engines, not the big SuperDracos, but they run off the same fuel supply and are mounted in the same pod. But if they ever need to do significant orbital maneuvers, I expect they'll light up the SuperDracos.

Comment: Re:Last time one was used? (Score 2) 50

by gman003 (#49625759) Attached to: SpaceX Testing Passenger Escape System Tomorrow

Because they're trying something new with it. They're using the same set of engines for emergency escape as they are for propulsive landing of the capsule. That's fairly innovative in and of itself, and the changes required for that (side rockets instead of a top-mounted tower) let it also be used for a longer period of the flight.

Comment: Depends (Score 1) 245

by gman003 (#49622609) Attached to: Is It Worth Learning a Little-Known Programming Language?

As always, the answer is "it depends on a lot of things":

1. Is the language little-used because it's a special-purpose language? UnrealScript probably doesn't crack the top twenty as far as general programming languages go, but in the game dev field it's probably one of the biggest. Using a specialized language for a specialized task is fine - usually even a good thing.

2. Is the language little-used, but library-compatible with a more common language? Clojure is a rare language, but it can call Java libraries and code, which is a massive boon. Actual programming languages don't matter so much as the libraries they allow you to use, and if you can piggyback on a bigger library of libraries, you can go far with a small, obscure language. This isn't sufficient to make the language OK to use, because:

3. Is the project going to be worked on by more than one person? Personal projects, sure, use whatever language you feel like. Small groups can decide what to use. But if it's a big project that's likely to cycle through developers, think about the impact using an uncommon language will have.

4. Is there something about your problem that makes common languages inefficient or ineffective? Is the uncommon language objectively better at the exact task you're solving? Or is it just "the syntax is slightly cleaner"? This isn't a full deciding factor, but unless the language shows promise as being useful in the future, I wouldn't use it on a personal project.

Comment: Any chance (Score 1) 121

by gman003 (#49617077) Attached to: Internet Customers Surpass Cable Subscribers At Comcast

Any chance Comcast will look at where their customers now lie, decide they're now an ISP with a side business in TV rather than a cable company with a side job in internet, and stop raping the quality of their internet to drive customers towards their cable offerings, and give up on those silly plans to become a competitor to Netflix et al. because they feel lonely without the ability to cram their own ads into something that's already overladen with advertising?

No chance? Didn't think so.

Comment: Re:The 30 and 40-somethings wrote the code... (Score 3, Interesting) 529

by gman003 (#49614129) Attached to: Recruiters Use 'Digital Native' As Code For 'No Old Folks'

"Digital Native" means you're obsessed with Facebook, Twitter, Instagram, Opentable, selfies, etc.

Weird, I'm a 90's kid and:
I haven't touched my Facebook account in years
My Twitter is mostly subscriptions, generally to things that are actually interesting (eg. @RealTimeWWII not @kanye)
I have no Instagram
I've never actually heard of Opentable
I've taken one selfie in my life, and it was a joke at my sister's wedding

I also used MS-DOS (via Windows 95, sure, but it still counts), think Perl is a more useful language than Ruby or any other fad-language-of-the-week, and I can read assembler if given enough time and a table of opcodes.

Do I still qualify as a Digital Native?

Comment: Only excuse should be too many other ports (Score 1) 301

The only excuse for having less than four should be having too many other ports present to physically fit them all.

Every current Intel mobile chipset provides at least four USB3 ports, and most provide six. The only acceptable reason not to have at least four is "between all these video outputs, audio outputs, Thunderbolt port, and SD card reader, there just wasn't room for all four USB ports".

The physical USB port costs basically nothing. You can get them for ten cents apiece on Amazon - I'm sure buying in lots of thousands instead of twenty will bring that down even further. Going above what the chipset provides adds an expense, of course, but 4-6 USB ports is enough. I just don't see a reason not to populate all of them with a physical port.

* Last-minute addition: another reasonable excuse is "we routed the USB port internally to the Bluetooth and Wifi adapters". Some motherboards do things that way, and that is indeed a reasonable excuse for having only two USB ports, if using a chipset with only four USB ports. But I would argue that if you know two ports will be used internally, you should probably spring for a 6-port chipset, particularly since only the cheapest limit to four.

Comment: Good idea, bad implementation (Score 4, Informative) 239

by gman003 (#49566461) Attached to: Valve Pulls the Plug On Paid Mods For Skyrim

Valve and Bethesda made numerous mistakes with this implementation, but I still consider it a good idea. I'm definitely planning to allow paid mods in my own games, if I ever get one ready for retail. But here's where they went wrong.

1) They set a minimum price far too high. Relatively few mods are worth a dollar, even the ones that are worth buying at all. Give supply and demand a free hand to set prices, and I think most average-sized mods would have been priced around $0.20. Some might have been able to sell at a much higher rate, but not many.

2) They didn't protect from fraud. As soon as the announcement hit, people started uploading mods they didn't make - there was already a massive corpus of free mods, after all, and basically no protection against this. The least they could have done is give a decent warning period, for mod authors to decide whether to start selling their mods or not, and to search for fake versions being uploaded without their consent. They didn't do that, and they definitely didn't do any sort of technical measures, like comparing uploaded mods' checksums against those already uploaded. All of that is easily foreseeable because I actually foresaw it - I've been planning how to do this in my own games, and all of that was on my list before they even announced their feature.

3) They didn't share the profit well. Valve was taking a 30% cut, which is already more than they do for full games, and then Zenimax was taking another 40%. I can see that, because the base game does a non-trivial amount of work for the mod, that they do deserve some compensation (although I'd say increased sales are the true payment to the publisher). But a cumulative 70% is just ridiculous. I'd argue that no less than 50% should go to the modder. For my own games with paid mods, I'm thinking more in the 75:25 or 90:10 range, or even 100% to the modder (because, after all, a vibrant modding community brings about more sales, so the marginal loss on hosting is more than recovered).

4) They launched it suddenly, with no notice. Nobody had any inkling it was coming, least of all the modders who would be most affected by it. Valve and Zenimax should have given at least the big-name modders some heads-up, so they could think and have time to rationally decide whether to start selling, and for how much, and to work out any licensing issues in multi-person teams. And perhaps if gamers had been able to see it coming, they could have realized it was a good thing, instead of letting the knee-jerk reaction control the debate.

They did, however, do one thing surprisingly right, which deserves recognition: they gave full, automatic refunds within 24 hours of purchase on any mod you didn't like. That's definitely something necessary, and something very surprising to see from Valve.

Hopefully they can sort out these issues with the next game they try this on, instead of giving up on what is an excellent idea.

Comment: Re:So (Score 2) 229

The point is to make the account cost more than the expected value gained via scamming.

Scams, in general, have a poor success rate. There may be a sucker born every minute, but there's 250 people born a minute. Even if a successful scam nets a large gain, losing $5 on each attempt makes it a losing proposition.

Comment: Re:Holy crap, that marketing spin (Score 1) 51

Uh, you sure you were searching for the Intel 750? Because Amazon lists it for $471 for the 400GB model, or $1200 for the 1200GB model. Which is quite a bit inflated from NewEgg's pricing but not exactly the $2400 you listed.

Oh wait, I should have read the rest of your post first. You have absolutely no idea what you're talking about, do you?

Comment: Focus on expert sites (Score 1) 276

by gman003 (#49501905) Attached to: Ask Slashdot: What Features Would You Like In a Search Engine?

I've started drifting away from using Google/Bing/whatever, in favor of loading a bunch of site-specific search engines into my search bar.

So if I'm looking for, say, a specific Magic card, I don't let Google search the entire net, and find everything that happens to say "elvish mystic", giving me a ton of irrelevant stuff (even searches like "mtg elvish mystic" bring up pages to buy one instead, which usually don't have the info I'm really looking for). Instead I click an extra button to go straight to Wizard's own database page for it.

Repeat that idea for about twelve different gaming wikis, plus Wikipedia for general knowledge, and you'll have the contents of my search bar. If I were into different hobbies, I might have similar search engines for those.

A single search engine that can figure out the context of the search, then go straight to the experts for that context, would be one way to do better than Google.

Comment: Re:Questionable engineering decisions. (Score 3, Informative) 75

by gman003 (#49501053) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

Uh, the SSME engines ran off the same propellant as the rocket - LH2 and LOX. It's a staged-combustion rocket - some of the fuel and oxidizer flow was diverted to a preburner, which partially combusted them (the mixture was fuel-rich, limited by oxygen), ran the fuel-rich exhaust through turbines for the fuel and oxidizer pumps, then exhausted into the main combustion chamber where it was mixed with the remaining oxygen to complete combustion.

A better example for a separate propellant would have have been the V2 rocket, which burned ethanol and LOX, and had a pump powered by hydrogen peroxide.

Right on all other points, though.

Comment: Re:Specific impulse versus thrust (Score 1) 75

by gman003 (#49500903) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

Not true. Measures of rocket efficiency almost always count losses to the pumps.

That's why gas-generator-pumped rockets (like the F-1, at 263s, or the Merlin 1D at 310s) are listed as less efficient than staged-combustion rockets (like the NK-33, at 331s). The rockets are measured as a full system, not at just the combustion chamber and nozzle.

This one, I would expect, has higher fuel efficiency per kg and lower thrust per kg. Not having to burn any fuel for non-propulsive purposes will undoubtedly help its fuel efficiency, but the heavy batteries will lower the thrust efficiency. That's just an educated guess though.

Comment: Cheap because of size, not engines (Score 2, Interesting) 75

by gman003 (#49500609) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

Big rocket engines use big propellant pumps. The pump on the F-1 (used on the Saturn V) ran about 55,000 horsepower.

Electric motors won't do that cheaper. And they'll sap the weight of the rocket, since even a dead battery is heavy. Fundamentally, a big rocket will be better served by a gas-generator or staged-combustion cycle.

That's fine for this rocket because it's so small. The payload is 110kg. For comparable rockets, turn to Iran's unflown Simorgh, Israel's Shavit, or North Korea's Unha, all in the 100-160kg range.

To put those numbers in comparison, let's look at SpaceX. The single-engined Falcon 1 put 670kg into orbit. A Falcon 9 runs 10,000-13,000kg. And the Falcon Heavy is supposed to lift 53,000kg.

Or for an older comparison, Sputnik 1 weighed 80kg, and Sputnik 2 weighed 500kg. So they're building a rocket that couldn't even lift the second satellite to ever fly. I'm not particularly impressed.

Maybe there's a niche for small payloads like this, but in all honesty, I expect you could fly several such payloads on one bigger rocket, or just hitchhike on the spare capacity on a big satellite launch. Still, worth a shot. Just don't pretend to be playing in the big leagues.

Comment: Holy crap, that marketing spin (Score 2) 51

"unlike Intel's new NVMe solution, the Kingston drive will work in all legacy platforms as well, not just Z97 and X99 boards with a compatible UEFI BIOS."

So it uses AHCI instead of NVMe, and tries to spin this off as a benefit over Intel's drive.




AHCI dates back to 2006. It was an improvement over IDE, but it was still designed for spinning rust. No parallel queues, a paltry limit of 32 queued commands, and a design that puts a pretty substantial load on the CPU for each command used. It's something like 14,000 cycles spent in just the driver code for an AHCI command - compare 10,000 for the entire OS stack from fread() to actual bits going over the line for NVMe.

Now, it is true that NVMe isn't fully supported on older motherboards. But that's only boot support - an NVMe drive will work as a data drive on anything running a current OS (Linux 3.3+, Windows 7+). And guess what? Most motherboards that have an M.2 slot* to begin with... are NVMe-compatible. So if you're buying an M.2 drive, you can probably use the NVMe drive. And if you're building a new computer, you'll be getting one that works with NVMe.

Backwards compatibility is important. I'm not saying to discontinue SATA SSDs. But making an M.2 drive that still uses AHCI, then claiming the backwards compatibility as a benefit, is just pure marketing bullshit.

* M.2 is a weird physical interface that can be connected to up to three different interfaces - PCIe, SATA and USB. The USB is only really used for wireless cards, so that leaves PCIe and SATA. Unfortunately motherboards don't have to wire both up to the slot. You can find some cheap motherboards with an M.2 slot that only works with SATA drives. I personally refuse to count those as full M.2 slots. And both Intel's 750 (the NVMe one) and Kingston's drive being advertized here would not work in such a drive, so my point about "if you can put this drive in your computer, you can put a 750 in there and have it work" stands.

This is now. Later is later.