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Comment: Precautions against unknown disease (Score 1) 57 57

The same thing can happen with another new disease that they don't know about, which in turn means they aren't screening for.

That's why most places (at least around here) also screen for behaviours which could end with blood borne disease spreading.

i.e.: You can't immediately donate blood after having a tattoo done.
Even if you are HIV negative, there might be another unknown disease that could have spread from improperly cleaned tools.
Need to way some time (1 year) before starting giving blood again.
By that time you'll have started showing symptoms and/or news of a new blood borne disease will have been heard.

Comment: Not "like every other" (Score 1) 102 102

Not exactly "So like every other prototype "hoverboard", then"

This one uses magnetic levitation. (Thus works only over a steel surface).

The one from the kickstarter project uses magnetic induction (Thus works over any conducting surface).

Get a bunch of engineers, split them into groups, and pack each group in a different room.
Ask them something awesome like an hoverboard, and they'll come out with probably a dozen of different solutions, each with its own advantage and short-comings. Including levitation solutions that explicitly work over water.

Comment: TRIM+NCQ (Score 1) 182 182

Except that's irrelevant, the guys didn't use queued TRIM either. It says in the article itself that they used non-queued TRIM.

They more precisley said :

The TRIM on our drives is un-queued

Which is true.

Except that, recent firmware fixes from Samsung (you know, the whole "speed decay on aging data" fiasco) had suddenly started to falsely report support for TRIM+NCQ.

So it might be possible that unkowningly to them, their Linux installation has suddenly started to issue queued TRIMs, even if the drive actually don't support them, because it trusts what the firmware told to do.

Comment: Indeed (Score 1) 182 182

Windows is doing it wrong {..} When Linux tries to follow the standard and do it right, it gets burned.

Indeed, that right: Windows doesn't support TRIM+NCQ, whereas Linux does and will enable it if the drive reports it as present.

the ssd manufacture has 'modified' their firmware to work around it. {...} and the ssd manufacture has 'modified' their firmware to work around it.

In this case it's purely accidental. Samsung issued a firmware upgrade for some Samsung SSD to fix a problem causing a decay of speed as data ages on the SSD. That new firmware happens to falsely report support for TRIM+NCQ whereas it doesn't actually support it.
It's a bug left in a new firmware fix, not a tweak intentionally designed to work around quirks and bugs in windows.

The bug doesn't trigger in Windows because windows doesn't support the feature. Linux (and BSD ?) do and are affected.

Comment: The thing Windows does (Score 1) 182 182

I have an 850 Pro at home and an 850 EVO at work, and haven't experienced any corruption. I know that Windows uses TRIM. Why am I not seeing any problems?

You're shielded from the problem because of 2 different things:

- Samsung 850 aren't as much affected by speed decay as Samsung 840. Thus a firmware fixing the speed problem was only shipped for 840s, not for 850s - and it's that firmware which had the problem. You drive simply didn't get the problematic firmware.

- That newest firmware falsely advertises that the drive supports TRIM together with NCQ. But the drive actually doesn't.Re-ordering should happen while TRIM is used.
Linux follows the standards: it asks the drive and only uses the feature that are advertised as supported. Because that specific firmware on that specific drive falsely reports supporting a missing feature, corruption happens.
Windows simply doesn't support TRIM with NCQ at all. The bug isn't triggered.

The current fix in linux is to put the drive on a blacklist and mimic Windows behavior by ignoring TRIM+NCQ.

So: The differences is that Linux uses TRIM+NCQ when instructed by the drive, whereas Windows doesn't. And your drive didn't happen to get the firmware that falsely report this.

Comment: TRIM+NCQ (Score 2) 182 182

it's not trim by itself that is problematic.
it's the combined use with NCQ (= reordering of commands).

The latest firmware (the one that fixes the speed decay) has started to falsely advertise support for this combination, whereas the drive doesn't actually support it.
The drive isn't actually able to re-order TRIM commands, and the wrong bit might end up being erased due to NCQ.

So this but will only show up:
- your drive is a Samsung 840 EVO (850 aren't affected by the speed decay and didn't get the faulty upgrade)
- if you have upgraded the firmware to the latest (faulty) version.
- you run an OS which is actually able to use TRIM+NCQ (Linux and BSD, basically)
- your OS also follows the standards (asks the drive what is supported and gets the false advertisement of TRIM+NCQ).
- you actually enable TRIM on the drive.

remove any one point of this chain and the bug doesn't happen.

Comment: TRIM vs NCQ (Score 1) 182 182

But if the drive was broken and someone had to write special software to fix it, how can you be sure that it was fixed correctly and completely? Can you also be sure that the "fix" works for all versions of firmware on the drive?

Because the fix is relatively simple.

To put in general terms:
- The problem is that the drive advertises a bunch of features. Linux tries to use them. But the firmware is buggy and the feature don't work or aren't even implemented.
- The fix is to ignore any advanced feature even if advertised by firmware. Stick to only the small subset of features that are also used in windows.

- the most frequent problem with trim is that the device advertises supporting TRIM with NCQ (= reordering of commands).
(the latest firmware for Samsung 840 EVO started advertising this in addition of fixing the speed decay).
Linux *can* issue TRIM together with NCQ. So when the drives says it does, it will start using it.
But the drives doesn't work with TRIM and NCQ combined. There's a bug in the implementeation, or the firmware doesn't even support it.
(no Samsung 8?? actually support TRIM+NCQ. It's falsely reported as present by the firmware).
- Windows (and perhaps Mac OS X) aren't affected by this because they don't support it to begin with.
- Linux fix is to simply ignore the falsely advertised TRIM+NCQ. It reverts to either use NCQ, or use TRIM in a blocking (slow) way.
And that is a permanent fix because is simply reverts to a behavious similar to windows. No new problem should arise in Linux because it simply mimics the behaviour of Windows. If anything was still broken, it would be affecting Windows too.
It will work against any version of the firmware (Linux isn't tricking the firmware or trying to compensate. Just plain ignoring missing features).

Of course, the best would be to use 100% standard compliant SSD.
But reality is that not much *are* actually standard compliant.

So unless you're ready to shell lots of money for some actually enterprise-grade SSD,
accepting SSD with patched support is the next best option.

Comment: Custom (Score 1) 78 78

Data can be exfiltrated by usb, just write it to a hidden folder and wait for the drive to come back around to you.

Which is specifically NOT the modus operandi of the majority of viruses aroudn (except a few like Stuxnet which had very specific targets).
Thus this would require writing custom code to address this very specific and unusual configuration.
So who's going to throw the ressources at writing a completely new virus specifically targetting the few movie sharing sneakernets around the world ?

As the poster above has noted: nobody. Nobody gives a fuck about Cuba and other such sneakernets.

There's no point in getting these machine or the data on them.
It's not worth blackmailing them. The cuban will probably earn even less money than the chinese guy who would have written the USB-transmitted ransom ware.
It's not worth trying to own the machine: you can't use it for DDOS nor Spam nor some alt-coin mining.
Whatever data they have probably concerns goods and money that are probably valued to 0.0001$ on your local market...

Comment: C++ vs paper and pencil (Score 1) 173 173

Seriously if C++ is the best we can do for *anything*, then we need to just throw in the towel and go back to pencil and paper right now.

Sometime, "pencil and paper" *are* the best tool for the job, because they work everywhere.

Same for C++:
It's maybe not Dart (for Google Chrome), nor Rust (for Firefox), nor Swift (latest gen iOS), nor whatever is the latest cool thing (scala ?) to run on a Java machine (for Android), nor Ruby (is that the lastest hipster thingy on servers ?)
But it works everywhere. Thus there *are* legitimate solution were using the older or simpler tool is better than all the modern hyped bells and whistles.

Comment: Alternatives for Skype in Linux (Score 1) 76 76

For quite some time, Eionrob has written a Skype plugin for purple (thus works in pidgin, adium, etc.)

Currently 2 versions available:

One requires the skype client running and uses the official Skype API to use it.
It still requires Skype, but at least it's being now routed to a half-decent client.
Voice calls work by opening a window from the original skype client.

The other version uses "Skype for Web".
It works thus 100% natively on any installation, without needing the original client.
Voice calls currently not implemented (because actually voice calls in "Skype for Web" aren't done with official web technologies, but using a proprietary binary plugin. But microsoft has mentioned considering upgrading that to WebRTC and such standards at some point of time in the future, so there's still hope)

Not perfect yet, buton the right track.

Comment: Movie Plot again ? (Score 2) 312 312

some asshole politician is going to try and use that as an argument against crypto-currencies

Googling around...
Apparently the story about this teen has been reported in the Washington post (among other).

I would have thought instead that this was straight out of Bruce Schneier's Movie Plot Threat Contest

Comment: No, it's all Snowden (Score 4, Funny) 546 546

It was all snowden's work along!
He stole the data for the sole purpose of giving to Russia and China!
He's an evil communist traitor that needs to be put on an electric chair!

The recent breach by China are just purely coincidental!

Also there's no way that Russia would the resource and know how to obtain such data, and they had to rely on a lone consultant instead of their mighty KGB/FSB !

Comment: 1st person DoA (Score 2) 79 79

Imagine a first-person-view Dead or Alive Xtreme Beach Volleyball. ^_^

First person ? Dead or Alive ?

You mean risking to get hit in the face by your (avatar's) own oversized breast due to jiggle physics turned up to eleven ?
That surely is going to be a wonderful first-person experience.

Comment: clamps (Score 1) 67 67

And all the steering wheels I've seen have special attachment to clamp/screw them on the table.
(See Logitech official page)

Are you forgetting about the force feedback? Without clamping the wheel to your desk the wheel is going to jump around like a piece of cooking popcorn and that's before you even get to the first corner.

Hence the clamp-attachement-thingy that is on nearly every single wheel I've seen, and that's clearly visible on lots of the picture on Logitech's official website.
They even have a paragrph about mounting it securely.

I suppose it might be possible with force feedback turned off but then what's the point?

To simulate the steering wheel of an actual real-world everyday car. You know, the things which got equipped with "Power Steering" for the past few decades, and which you can almost steer around with a single finger. :-D

("Reality Is Unrealistic" trope again).

(Well I get the point that the "racing wheel" are for playing car racing games, which simulate cars with differently configured steering column.
But still, a steering wheel with the forcefeed-back turned as low as possible is the closest thing to the normal car that you use to drive around)

I know engineers. They love to change things. - Dr. McCoy