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

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: Blame posix (Score 1) 233 233

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

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

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

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

"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

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

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

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

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

Comment: Re:Specced too low, weird form factor (Score 1) 174 174

This is the *mobile* i5, not the full blown desktop i5. It's basically the Broadwell successor to the Haswell 29xx series. 15W TDP or less. The BRIX runs 8W idle (not sleeping) and 20W at 100% cpu (all 4 threads full out). Intel is playing fast and loose with their naming schema for Broadwell.

-Matt

Comment: Re:Specced too low, weird form factor (Score 1) 174 174

All the older haswell-based boxes have dropped in price significantly. They make decent boxes too as long as you are not compute-heavy. E.G. the 2957U is 2-core, no hypthreading, 1.4 GHz, no-turbo, and no AESNI (so https and other crypto is slow). Whereas even the Broadwell i3-5200U is 2-core/4-thread, 2.2 GHz with Turbo to 2.7 GHz, and has AESNI.

I have an Acer C720P chromebook running DragonFly (BSD) with the 2955U in it, which is very close to the 2957U. I would call it decent for its purpose and it can certainly drive the chromebook's display fairly well. Firefox is not as snappy as I would like, though.

On the i5-5200U even unaccelerated video decoding can run full frame at full speed on my 1920x1050 monitor and firefox is quite snappy.

If I had to make a cost-concious decision on using the older Haswell based cpu and giving up some cpu power I would say that it would still be a reasonable choice *BUT* I would compensate at least a little by throwing in more ram (at least 4GB).

-Matt

Comment: Specced too low, weird form factor (Score 2) 174 174

It's specced way too low to really be useful as a general computing device, and the form factor is 'weird' to say the least. It's too big to really be called a stick, and too small to be able to pack a decent cpu. There's plenty of space behind the monitor for a somewhat larger device in a better form factor. The stick is a play toy that you will become disappointed with very quickly (think the old 'netbook' concept Intel tried to push a few years ago... that's what the stick feels like).

Honestly, the 'compute stick' makes zero sense for a TV-mounted device. It is far better to just go with a chrome cast stick or an AppleTV for airplay and using a pad or cell in your hand to control it if you want to throw a display up on the TV. Otherwise you will be fumbling around with a horrible remote or you have to throw together a bluetooth keyboard (etc...) and it just won't be a fun or convenient experience.

My recommendation... don't bother with this gadget. Instead, spend a bit more money and get an Intel NUC or Gigabyte BRIX (both based on Broadwell). And get at least the i5 version, the lack of turbo in the i3 version is telling. e.g. i5-5200 based box or better. It will cost significantly more than the stick, but it packs a decent cpu, can take up to 16GB of ram (2x204pin SO-DIMM DDR3), and depending on the model might even have room for a 2.5" SSD or HDD in it. The broadwell i5-5200U makes for quite a reasonable compact workstation and boxes based on it will be almost universally dual-headed. Of course, whatever floats your boat but I would definitely say that the lowest-priced Intel NUC or Gigabyte BRIX that is haswell-based or broadwell-based is still going to be an order of magnitude better than the compute stick.

I have one of the Gigabyte GB-BXi5H-5200's myself ('H' version fits a normal 2.5" SSD or HDD) and packed 16GB of ram into it. It is dual-headed so I can drive two displays with it and the box is small enough to mount on the back of a monitor if you so desire (it even includes a mounting plate and most monitors, such as LG monitors, are ready to take it). And if mounting it on the back of a TV doesn't make sense, mount it on the back of a monitor instead or just let it float behind the monitor. It's a small box, after all, it won't get in the way of anything. 4-thread (2-core), 2.2 GHz turbo to 2.7 GHz. Dual-head. Decent.

-Matt

Mirrors should reflect a little before throwing back images. -- Jean Cocteau

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