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Comment Re:It'd better happen quick then (Score 1) 311

The primary reason why most laptop vendors don't offer a hard drive in place of the optical drive is power consumption. Optical drives use basically nothing when they're sitting there idle, and since most optical drives today are used about as much as floppy drives were used in the mid 1990's (i.e., virtually never, only to install software, and even that is going away with Internet delivery of software), that means that they can spec the rest of the laptop around a lower power draw, which allows them to claim a longer battery life and allows them to use a smaller fan to cool the laptop and a smaller brick to power the laptop and allows you to actually set the laptop on your lap without scorching your lap and requiring a trip to the surgery suit for skin grafts. The large desktop replacement laptops from Dell and HP (amongst others) actually do have space for multiple hard drives, but those are more portable desktops than laptops -- you aren't going to unplug one of those and walk across the lab with it to plug into a different network to sniff for a rogue machine that's brought your installation to a crawl, they sit on a desk and stay there, with short excursions to the car and home perhaps, because they are large, bulky, hot, will last maybe 20 minutes on battery power, and have power bricks the size of concrete blocks.

Given that, if you need a lot of space in a single 2.5" form factor package to fit into, say, a current Apple Macbook Pro (where Apple very highly optimizes the power consumption and the OS really doesn't deal well with you removing the optical drive and putting in a second hard drive using a third-party bracket, it won't go to sleep correctly much of the time), the hybrid approach makes a lot of sense. The primary issue with the prior generation of the Momentus XT in that application was a) it topped off at 500GB, and b) it consumed more power than a 750GB 7200 RPM Western Digital Black drive. The current generation solves the capacity problem, but I'll need to take a close look at power consumption, because power budgets in many modern slim (i.e., actually portable) laptops are quite tight.

Comment Hybrid can actually be sometimes faster (Score 1) 311

The core problem with SSD's is write speed on workloads that have a large number of small updates. My testing on the older 500GB Momentus XT showed that in general it had better write speed doing, e.g., a Fedora install, than the 80GB Intel SSD that I benchmarked it against (same generations of product here, about a year ago), due to the large number of small updates that the non-SSD-aware EXT3/4 filesystems do during the course of installing oodles of RPM's. Because the Momentus only caches *read* requests in the SSD (write requests flow right through it, other than to invalidate anything in its internal cache that is getting written), writes went through at full 7200 rpm 2.5" hard drive speed. In general when I benchmarked writes on similar-generation 7200 rpm 2.5" hard drives and SSD's, the hard drives ended up faster for virtually all real-world workloads, so the end result of my benchmarking was that on real-world workloads the hybrid drive was faster at reads than a hard drive (primarily due to SSD-cached filesystem metadata) and faster at writes than an SSD.

Please not that I have *not* tested the current generation of SSD's and Momentus XT. Just that it's baffling that the Momentus XT never seemed to really get any traction in the marketplace, given the performance advantages of the approach for many real-world tasks.

Comment Will the file formats be publicly documented? (Score 4, Insightful) 186

This would be a good time to write your congresscritter to point out the problems with undocumented file formats as well as Apis and network protocols.

There are plenty of formats that could be used that are open and vendor neutral.

If congress doesn't require that in it's funding authorization, many of our public records will be stored as word dos or in ms SQL databases.

Comment I don't generally have coworkers or managers (Score 1) 275

I do almost all my projects completely on my own. I'm lucky if my clients devote more effort to their specs than tossing some chicken entrails on the back of a used envelope then mailing it to me.

I'm sick to death of consulting. Until I can get a perm job I do most of my work from wifi spots so I can be around the rest of humanity.

Comment Re:teachers make the difference (Score 1) 292

Wow, great job reciting Fox News talking points. Too bad they have nothing to do with reality. I know what my local school districts' pay scale is. I know what I get paid as a top software engineer. I know what my benefits are, and I know what my local school districts' benefits are. Here's some facts:

* I get free health, dental, life, and disability insurance as a software engineer. Teachers in the local district pay 100% of the cost of their health insurance.
* The top pay scale for a teacher with 20 years experience and an advanced degree in my district is less than half of my salary as a software engineer.
* Tenure rights for public school teachers are based on Constitutional due process and as long as due process is followed, any teacher can be fired for any *valid* reason (i.e., not just because the principal doesn't like gays or Mormons). Any principal who says he has a problem getting rid of an incompetent teacher is either himself incompetent or is lying to you, there is due process to follow but in every state of the nation an incompetent teacher can be fired regardless of tenure.
* Tenure rights don't have anything to do with layoffs. 40% of teachers in some of our local districts got layoff notices this year. A large percentage of those teachers had tenure.
* I will receive more money from Social Security when I retire (due to maxing out the contribution limit each year) than the teachers in the top pay scale at my local district will receive from CALPERS. And because of the double-dipping penalty in the Social Security formula, they'll never make more combined pension and Social Security than I get from Social Security when I retire.

Really, with a disrespectful and ignorant attitude being the norm, why *would* I want to teach? So people like you could spit on me for doing a job that's ten times harder than software engineering? Been there, done that. No thanks.

Comment Re:teachers make the difference (Score 5, Informative) 292

I am wondering what in the world you are talking about. During the three years I was teaching, a) my highest salary was the munificent sum of $21,800 per year (roughly $40K/year in today's dollars), b) I paid 100% of my health insurance costs (NO district subsidy of the cost), and c) the retirement benefit was 40% of my ginormous salary if I managed to survive 30 years without stroking out, being knifed or shot by one of my students, or being thrown under the bus by a school administrator upset that I cared about whether my students learned or not (and note that I did NOT pay into Social Security and if I had managed to get Social Security via some other job, there's a "double dipper" penalty in the SS formula that would take most of that away from me). In the years since I switched to doing software engineering rather than teaching mathematics I've sometimes worked 60+-hour weeks and multiple all-nighters but never worked anywhere near as hard as I worked as a teacher and get paid more than three times as much money than a teacher. If you paid me the same six-figure salary I make as a senior-level engineer I still wouldn't go back, because the job is thankless, never-ending, and utterly exhausting both physically and intellectually if you're doing it right. My hats off to those teachers who stay on the job and do it well, year after year, because the fools who criticize such teachers have not a clue.

BTW, once you get above 35 students in a classroom, it becomes simply impossible to manage in a way conducive to learning. Above 35 students learning starts dropping off rapidly, past 40 it's just baby-sitting and make-work. Teachers know this the hard way. The fact that politicians and parents talk about 40+ student classrooms as if that were some reasonable solution to the cost of running public schools tells me that either a) they don't care about education, they just want free babysitting to keep kids off the streets, or b) they're clueless cretins who need to be drummed about the head with a clue stick. That is all.

Comment Re:Want videogame studios? (Score 1) 292

Perhaps Media Molecule should think about hiring some of the 50%+ of UK Computer Science graduates who cannot find a job in the field? When I see statistics that say that 70% of Computer Science graduates are not working in the field five years later, I call balderdash on the notion of a shortage of software engineers in the UK. If Media Molecule truly believes that 50%+ of UK Computer Science graduates are unqualified to write software, it sounds to me as if their beef is with the universities that credential people not worthy of said credential, not with anything happening at the primary school level.

Comment Re:Superheros are trained young (Score 1) 292

I saw my first computer at age 17. I've been making a living writing software or doing other related things for over 20 years now and while I'm no Linus Torvalds, I still don't have any problem finding a job when I need one and making significant contributions everywhere I go. What differentiates those who will be good at writing software from those who will never be has nothing to do with how young you are when you encounter computers, and everything to do with your ability to think in a logical and straightforward manner. I would much rather see our schools teach thinking skills than computer skills. Thinking skills are useful for other things (say, in figuring out which politicians are lying to you and thus you should vote for the one *not* lying to you, for example), while skill writing computer programs is useful only for a small set of problems. I don't write algorithms to go grocery shopping or change the cat box. Just sayin'.

Comment You cannot walk through a wormhole (Score 2) 199

you'll come out the other side as a largely random sequence of random types of fundamental particles, mostly photons. trust me. while I only playvacsoftware engineer on the Internet, I really am a physicist.

you could through one though.

I spent quite a long time puzzling overbhowbto encode a signal so that any alien that was capable of detecting it would bevquite certainbwas transmitted by intelligent beings. just for our signal to be nonrandom would be insufficient, as there are many physical processes that generate powerful nonrandom signals. pulsars are quickly rotating, highly magnetic collapsedvstars, butvwere thought at first to be signals from alien civilizations.

you also need a way for your signal to stabbed out from the enormous radio noise of the sun.

transmit pulse sequences with the number of pulses being a prime number withba modest pause in between. pause in between each sequence then transmit the next larger prime number. repeat until you get to a very large prime then startbover again with two.

to overcome solar noise, use an interferometer. two antennas spaced far apart have the same resolution as a single antenna as wide as the distance between the two. if you control the relative phase of your antennas you can focus yourvtransmittedvsignal with the same resolution. the focussed signal would appear more powerful than the sun's signal because it diminishes with the square of the distance.

such antennas could be placed in solar orbit at the earths lagrange points, with solar or nuclear power. they could transmit in many different directions simultaneously by altering their phases.

Comment only low frequencies bounce off the ionosphere (Score 1) 199

that's cities have fm radio but rural radio stations are generally the lower frequency am.

which tesla coils are driven by sixty hertz alternating current, they get their incredibly high voltage by preventing a large inductance from conducting. inductors are current source that will develop any voltage necessary to continue conducting. eventually there is a powerful but very short-lived arc that also generates a very high frequency radio signal.

that's also why you shouldn't mess with large inductors if you don't know what you're doing. when high energy electrons strike the inner orbital electrons of high atomic number electrons the photon that's emitted from the collission is an x-Ray. that can give you Th3 C4nc3r.

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