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Comment: Beta is gone (Score 1) 12

by flux (#49154257) Attached to: Engineering Update 2-27-2015

For me was way nicer than the current main site, and in fact I removed from my web browser history so that slashdot-arrow-down would bring me there instead. Sad to see it gone.

I imagine some of its features will be eventually brought to the main site, but as history has shown, the vocal /.tters are allergic to change.

Comment: Re:Comment (Score 1) 168

by flux (#49010337) Attached to: Employees In Swedish Office Complex Volunteer For RFID Implants For Access

They get the energy and the clock signal from the 'receiver'. So they don't even need a crystal. But as long as they have those two available, they can perform any kind of computations. As longer computations need more clock pulses, it could be that advanced crypto algorithms could increase the time-to-validate annoyingly.

Comment: Insecure? (Score 1) 168

by flux (#49010323) Attached to: Employees In Swedish Office Complex Volunteer For RFID Implants For Access

Doesn't seem actually quite that easy though in practice. Some RFID tags employ a challenge/response mechanism.

If someone does have such a solution available, though, I'm interested! A colleague tried to reuse the tags at work for some other purposes by writing a custom reader for them, but I think he gave up due to those issues.

Comment: Re:Unfamiliar (Score 1) 370

by flux (#47883689) Attached to: The State of ZFS On Linux

It's performing a checksum of your entire system. That's going to be a CPU hog. BTRFS will be no different in this regard.

Well, my btrfs scrubs 1.3 gigabytes per second and chances are it's IO-bound on the RAID10 SSDs, so if ZFS scrubbing performance is comparable, I would say it's not a CPU hog.

You can add a new disk to a pool. You can add a new mirror or Z vdev to a pool.

You make it sound such a petty limitation. But if you do have 5-device raidz and a pool, you are not going to add a single device to the system without risking data durability, you need to add at least two so you can mirror them, and then you're wasting space compared to parity-raids.

Comment: Re:Battery consumption due to CPU? (Score 1) 87

by flux (#47837193) Attached to: Moto 360 Reviews Arrive

Meh, I was hoping some kind of dim OLED MIP display that would display always, like in N9 (though I did notice it was not mentioned in the specs) - it would have explained why most of the clock displays had dark background.

There are accelerometers that can queue many samples and then pass them to the CPU in one go (ie. 100 samples) and in addition they can have thresholds for interrupts. If your CPU is going to be woken once a second - assuming 100 Hz sampling rate, which is quite nice - then it doesn't really sound that bad, unless you have bad power saving functionality either in the CPU or in the operating system.

I suppose BLE doesn't need to take that much energy either if you grant a few seconds latency from notifications to actually displaying them.

There's always hoping they can improve the battery usage with firmware upgrades..

Comment: Battery consumption due to CPU? (Score 2) 87

by flux (#47835253) Attached to: Moto 360 Reviews Arrive

Everyone keeps saying how this doesn't have the latest most powersaving CPU but how much CPU does this device even need? Once a second to update the hand? Or could even be a few times a minute for a smooth minute hand.

I would be surprised if the overwhelming majority of the amperage doesn't go to the display and the BLE radio (in that order), the CPU coming last.

Comment: Circular LCDs (Score 1) 87

by flux (#47835201) Attached to: Moto 360 Reviews Arrive

The addressing of LCDs is inherently cartesian, but I don't see why it means the display itself must be as well. The space not on the display is not wasted, there are not physical pixels being hidden here. Instead, the device provides the user with more free physical space compared to one with square screen, not to mention nicer look.

Comment: Re:Proof (Score 2) 82

by flux (#47563723) Attached to: seL4 Verified Microkernel Now Open Source

While there have been some Linux bugs due to the compiler, I can't really recall hardware problems that have caused security problems â" unless you already have physical access, and then all bets are off.

The compiler issue could be addressed by using a certified compiler, such as this: . Sadly CompCert is not FOSS.

"It ain't so much the things we don't know that get us in trouble. It's the things we know that ain't so." -- Artemus Ward aka Charles Farrar Brown