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Comment: Section 2 of the voting rights act REQUIRES D gerr (Score 2, Interesting) 293

by raymorris (#48478969) Attached to: Mathematicians Study Effects of Gerrymandering On 2012 Election

> If I'm wrong, please do show me this mass D gerrymandering that's going on.... Or did go on.

Section 2 of the Voting Rights Act _requires_ that districts be gerrymandered such that demographic groups which are a _minority_ of the population make up a _majority_ of the voters in those districts. When states fail to gerrymander for democrats ^H^H^H^H^H^H^H^H^H^H black people, the federal government intervenes and forces gerrymandered districts. This is not new.

Comment: Cache and NCQ already this (Score 1) 195

by raymorris (#48475835) Attached to: Consortium Roadmap Shows 100TB Hard Drives Possible By 2025

This cache and especially native command queuing (ncq), the drive ALREADY has to pay attention to the sequence in which operations are carried out. A read requested first, then a write, might already be done in reverse order, requiring a check that the sector read isn't the same one written.

I don't see any reason reading and writing two sectors at a time makes any fundamental difference.

Comment: trillions of bits, why one head per platter? (Score 5, Interesting) 195

by raymorris (#48472441) Attached to: Consortium Roadmap Shows 100TB Hard Drives Possible By 2025

Somewhat off topic, but while we're talking about drives:

We put millions of transistors on a chip. Millions of photodetectors (pixels) in your phone's camera, a million pixels on it's display. Yet our hard drives have ONE sensor that swings back and forth on a mechanical arm?!?! Why the heck isn't the read/write head a strip, with a few thousand "pixels", so it can read any sector as the platter spins beneath it, without swinging the heads back and forth? That would eliminate seek time.

  If needed, you could move the strip back and forth a thousandth of an inch to align a head with one of it's four tracks. That'd be a lot quicker that moving the head a full inch as they do now.

So presumably there is some good reason that can't be done. Still, an additional arm exactly like the existing one, but on the opposite side of the platter, would cut rotational latency in half and increase throughout up to 100%. Seems like an easy win.

Comment: devil's advocate: bio for 200 people (Score 1) 125

by raymorris (#48472037) Attached to: Ask Slashdot: Best Biometric Authentication System?

Although I tend to agree with the general consensus that RFID or even QR codes would be a simpler way to identify (not authenticate) people, there is one important nuance being missed in all the criticism of biometric.

In the most common use cases for biometrics, you're attempting to distinguish this one person vs the other 5 billion people in the world. That's hard. This particular use case is much simpler - we're judt asking it to distinguish betweenthe 50 or so people who work in this clean room. In other words, we know it's one of these 50 people, which of them is it? That's a much easier question, so high accuracy should be easy to achieve with the right settings.

Comment: yep, crashing traditional RC is expensive, and com (Score 1) 19

by raymorris (#48471145) Attached to: Fly With the Brooklyn Aerodrome (Video)

Indeed, this approach is interesting to me because I had to get out of RC planes due to the cost of crashing, especially while I was first learning to fly. Anything that allows one to recover from a crash with just a few dollars and a few minutes is a win.

This approach reminds me of a popular design that is also inexpensive, but this new design has two advantages. First, it positions the motor and prop in the center, where it is protected from damage. Second, they mount the electrical components on a subassembly board, allowing the entire assembly to be moved to a new body as one unit, thereby saving time.

Comment: Most popular 840 Pro warranted for 73 TB (3 days) (Score 1) 428

by raymorris (#48466483) Attached to: How Intel and Micron May Finally Kill the Hard Disk Drive

> You'll be hard pressed to find a drive that isn't guaranteed for 5 years of writes at the maximum throughput the drive can handle.

Hah! I wish. The most popular line of SSDs is the Samsung 840 series. In commercial usage, the 840 Pro is warranted for 73 TB written. That's 3 DAYS at maximum throughput.

The 850 series is warranted for twice as much - 150 TB, or one week at maximum throughput.

Comment: fast access allows other uses, like instant compar (Score 1) 275

by raymorris (#48464537) Attached to: Is LTO Tape On Its Way Out?

That near-instant access also allows other uses. For example, when a small business client's web site is defaced or simply broken, I can run rsync --dry-run and tell them exactly which files have changed - in minutes, while they're still on the phone. I can restore the damaged files just as quickly.

Tape has it's place, but online offsite backups, done right, have some very significant advantages too.

Comment: Constant writes such as backups, security cameras (Score 1) 428

by raymorris (#48463961) Attached to: How Intel and Micron May Finally Kill the Hard Disk Drive

> Would you buy those 15k's new today? What usage pattern would favor 15k's vs ssd's?

Anything that keeps the drive fairly busy writing. Our particular application is backups. Our backup servers write pretty much constantly. SSDs might last a couple of years, they might not.

DVRs for security cameras are another example application that writes pretty much constantly, so again HDDs are a better fit.

On the other hand, SSDs are a much better fit for most laptops, where you want fast boot and physical durability. Each is the right tool for certain applications.

Comment: Quotes: synonyms and phrases (Score 1) 127

by raymorris (#48461329) Attached to: Attack of the One-Letter Programming Languages

I believe quotes require that exact phrase, in order. Traditionally, that is useful for multiple-word phrases. Since Google will by default include synonyms, quotes (exact phrase) can also be useful to avoid synonyms with even a single word quoted.

The plus sign appears to still require a specific word, as it always has. This is most useful when you want to search for what appears to be an unimportant word like "the" or you have many search terms and some terms are most important.

Comment: wrong too. Programmer vs knows a language (Score 1) 127

by raymorris (#48456863) Attached to: Attack of the One-Letter Programming Languages

That idea kind of wrong, too. For maintenance tasks, more than once I've sat down and fixed code without ever having seen the language before, sometimes without bothering to check which language it is. A decent programmer isn't going to have to much trouble maintaining any reasonable language. For example, a fence post error is a fence post error in any language, and the fix is always the same - use the value one less.

Comment: US STILL sends aid to China to subsidize solar (Score 1) 91

by raymorris (#48444715) Attached to: How "Big Ideas" Are Actually Hurting International Development

> China didn't receive any fucking foreign aid from nobody

They actually received billions in foreign aid, cash from the US and subsidized loans from Japan. Aid to China has dropped dramatically over the last 30 years, but USAID is still sending taxpayer money to China to subsidize their green energy industry. At the same time, the US is suing China for illegal subsidies to their solar industry, which violate trade agreements.

So the current standard operating procedure in the US is:

Make a trade deal woth China agreeing to no subsidies to companies engaged in international trade.
Borrow money from China.
Give that money back to China, on the condition that they use it to subsidize green energy companies.
Sue them for subsidizing the green energy companies.

There is no royal road to geometry. -- Euclid