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Comment: Re:Wealth inequality (Score 1) 937 937

by m.dillon (#49981843) Attached to: The Vicious Circle That Is Sending Rents Spiraling Higher

For renters it is pushing out people with lower incomes. Not everyone (due to rent control in areas), but still quite a lot of people are getting pushed out I think.

For existing lower-income homeowners it creates an opportunity to get a really good price for their home and then move to cheaper environs. (aka Gentrification).

The remaining pre-existing homeowners are not necessarily going anywhere. Prop 13 means that their property taxes are not changing radically and living costs are otherwise on a less steep ramp.

Gentrification is a two-edged sword, for sure, but I'm not sure that anything can really be done about it. The people protesting the changing nature of their neighborhoods are in the same economic class as many of the people selling and moving away. A person from group A can't really force a person from group B to not sell their home.

-Matt

Comment: So, clarify this for me... (Score 1) 280 280

by Brian Kendig (#49956059) Attached to: Windows 10 Will Be Free To Users Who Test It

- If I do a clean install of Windows 10 Preview onto a computer, that will turn into a full license of Windows 10 on July 29, no upgrade from a previous version of Windows is necessary? Or does this only apply if I've installed Windows 10 Preview onto an installation of Windows 7 or 8.1?

(http://blogs.windows.com/bloggingwindows/2015/06/19/upcoming-changes-to-windows-10-insider-preview-builds/ is unclear on this, saying "As long as you are running an Insider Preview build and connected with the MSA you used to register, you will receive the Windows 10 final release builld" but then "It’s important to note that only people running Genuine Windows 7 or Windows 8.1 can upgrade to Windows 10 as part of the free upgrade offer.")

- I only see Windows 10 Preview releases for x86 and x64. How do I get the Pro version instead of the Home version?

I see this as a good way that I can get free up-to-date Windows licenses for old computers I have that are running XP and Vista; all I need is to wipe them and put Windows 10 Preview on them, and link them to my Microsoft account. I just want to make sure that this will work, and I'd like to have the Pro version.

Comment: Blame posix (Score 1) 232 232

by m.dillon (#49947153) Attached to: June 30th Leap Second Could Trigger Unexpected Issues

Blame posix for making all the goddamn pthread *_timedlock() calls take an absolute real time instead of a monotonic clock.

In anycase, I'm not even going to bother doing anything fancy. I'll let the system suddenly be one second off and then correct itself over the next hour. I'm certainly not going to do something stupid like letting the seconds field increment to 60. Having the ntp base time even go through these corrections is already dumb enough. Base time should be some absolute measure and leap seconds should just be adjusted after the fact in a manner similar to timezones.

-Matt

Comment: TRIM -- command of mass destruction (Score 5, Interesting) 182 182

by m.dillon (#49925023) Attached to: TRIM and Linux: Tread Cautiously, and Keep Backups Handy

The only TRIM use I recommend is running on it on an entire partition, e.g. like the swap partition, at boot, or before initializing a new filesystem. And that's it. It's an EXTREMELY dangerous command which results in non-deterministic operation. Not only do SSDs have bugs in handling TRIM, but filesystem implementations almost certainly also have ordering and concurrency bugs in handling TRIM. It's the least well-tested part of the firmware and the least well-tested part of the filesystem implementation. And due to cache effects, it's almost impossible to test it in a deterministic manner.

You can get close to the same performance and life out of your SSD without using TRIM by doing two simple things. First, use a filesystem with at least a 4KB block size so the SSD doesn't have to write-combine stuff on 512-byte boundaries. Second, simply leave a part of the SSD unused. 5% is plenty. In fact, if you have swap space configured on your SSD, that's usually enough on its own (since swap is not usually filled up during normal operation), as long as you TRIM it on boot.

-Matt

Comment: Sheesh, 4K isn't obsolete yet! (Score 1) 181 181

I mean, come on... just when the graphics performance starts to get good, people all want bigger displays which halves the performance and then want to go even BIGGER and halve it again.

My perfectly good Sandybridge i7 can't drive this shit. Time to rotate in another workstation. Again.

Grumble.

-Matt

Comment: He's screwed if he didn't file a gift tax form (Score 2) 510 510

by m.dillon (#49832463) Attached to: Why Is It a Crime For Dennis Hastert To Evade Government Scrutiny?

I'm going to guess that he didn't file a gift tax return with the IRS for the millions he gave to person X. In which case he's up for tax evasion.

There's a certain degree of paranoia involved here as well. But this law isn't even the most onerous in the U.S. The worst one is the police confiscation laws that were originally intended to be anti-trafficking tools but now tend to be abused rather badly.

http://www.npr.org/sections/th...

-Matt

Comment: Re:Laser gun.... who knows. Railgun though (Score 2) 185 185

by m.dillon (#49720629) Attached to: Navy's New Laser Weapon: Hype Or Reality?

I think currently demonstrated ship-mountable railguns can emit a 7+ pound projectile at Mach 7. More to the point, these can be kinetic projectiles, meaning no explosives required, and there's more room for other things like, oh guidance systems.

Good luck evading that.

-Matt

Comment: Keychain (Score 1) 278 278

by m.dillon (#49703663) Attached to: Ask Slashdot: What's On Your Keychain?

"Heartbeat monitor with a deadman's switch which blows away all my encryption keys."

ok... Maybe not.

"Car keys, house key, lead-line isotope container for when I need a distraction."

Hmm. Let me redact that.

"Car keys, house key, LED flash light, tag with 2D barcode with a virus URL in case someone is too curious."

There. That sounds reasonably sane.

-Matt

Comment: Re:Backups (Score 1) 184 184

by m.dillon (#49660973) Attached to: Enterprise SSDs, Powered Off, Potentially Lose Data In a Week

No, its a stupid recommendation. Spinning rust doesn't last very long on a shelf. It will rapidly go bad mechanically if you keep switching between shelf and active. SSDs are far superior and data retention is going to remain very high until they really dig into their durability. If you still care, there's no reason why you can't just leave them disconnected from a computer but still powered... they eat no real current compared to a hard drive. SSD-based data retention should be 30+ years if left powered... impossible to test as yet :-)... but no reason why not.

However, for backup purposes there is still an issue of cost. Using SSDs for bulk backup storage can be expensive... it wouldn't matter for a big business so much but cost can be a big issue for individual users.

SSDs don't go bad the way HDDs do. With a HDD maximum reasonably-safe life is 3 years whether powered or not (and swapping between powered and shelf will radically reduce its durability). With a SSD only durability really matters. A business can easily justify buying the required SSD storage in bulk with a marginal cost calculation, but it might be too big a hunk of change for an individual.

Personally speaking I still use HDDs for my backups, for reasons of cost, but I expect in the next few years that will change as SSD prices continue to drop. I just bumped up from 2TB x 3 (active, on-site backup, off-site backup) to 4TB x 3. My storage needs are going up more slowly than the technology is dropping in price. The two will meet in a few years and I'll be 100% SSDs. I'm already 100% SSDs for everything else. No point even contemplating a HDD any more except for bulk backup storage or software test rigs.

-Matt

Comment: Re:toy anyway (Score 1) 65 65

by m.dillon (#49659665) Attached to: Samsung's SSD 840 Read Performance Degradation Explained

Actually, more and more SSDs today *DO* have power loss protection. Take it apart... if you see a bunch of capacitors on the mainboard all bunched together with no obvious purpose it's probably to keep power good long enough to finish writing out meta-data. Cheaper to use a lot of normal caps than to use thin-film high capacity caps.

-Matt

Comment: Re:Strange Linux behavior (Score 1) 65 65

by m.dillon (#49659623) Attached to: Samsung's SSD 840 Read Performance Degradation Explained

This is not related to the SSD. If your cpus are pegged then it's something outside the disk driver. If it's system time it could be two things: (1) Either the compilers are getting into a system call loop of some sort or (2) The filesystem is doing something that is causing lock contention or other problems.

Well, it could be more than two things, but it is highly unlikely to be the SSD.

One thing I've noticed with fast storage devices is that sometimes housekeeping operations by filesystems can stall out the whole system because the housekeeping operations assume the disk I/O will block when, in many cases, the disk I/O completes instantly and essentially does not block, causing the kernel thread to eat more cpu than intended.

-Matt

Comment: There's no news here. (Score 1) 184 184

by m.dillon (#49659099) Attached to: Enterprise SSDs, Powered Off, Potentially Lose Data In a Week

These tests explicitly state that the SSD is rewritten until it reaches its endurance rating before the retention test is done. At that point the flash in a consumer would not be expected to retain data unpowered for more than 1 year.

If you write your data to a fresh SSD once, multiply the number by at least 10.

-Matt

"It is better for civilization to be going down the drain than to be coming up it." -- Henry Allen

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