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Comment: Re:Why ext4 (Score 1) 223

by Rich0 (#49748219) Attached to: Linux 4.0 Has a File-System Corruption Problem, RAID Users Warned

Agree, as the other reply pointed out as well. And you can do the same with mdadm raid too (though obviously with none of the benefits btrfs/zfs bring for data integrity like checksumming and copy-on-write). Mdadm will also let you reshape an array in place (that is change raid levels or number of disks), though with mdadm that will often result in messing up your stripe alignment and of course it is more likely to eat your data if something goes wrong since if it finds a parity mismatch it has no way to know which copy is bad.

I was just commenting that btrfs tends to have a lot of features that appeal to small system users that you'll actually find missing on zfs, even if it is far less mature overall, and lacking in many enterprise-scale features. It just reflects the emphasis of the developers behind it.

I really can't complain about zfs - it is a great filesystem. However, things like not being able to reshape an array or mix disk sizes in an array are some of the things that hold me back from adopting it. Heck, btrfs will let you switch from raid1 to raid5 without touching any of the data already written - newly-allocated chunks will use raid5 and existing chunks will continue to use raid1 - it doesn't manage arrays at the whole-device level. In practice though you're likely to tell it to rebalance your data of course.

Comment: Re:Why ext4 (Score 1) 223

by Rich0 (#49748169) Attached to: Linux 4.0 Has a File-System Corruption Problem, RAID Users Warned

Sure, but with btrfs you can just add one drive and sometimes get its entire capacity added to your array - it works fine with mixed-size disks.

Of course, it might just decide not to boot the next day, and that is the downside to btrfs. It does tend to be a bit more friendly in scenarios where you have a small number of disks, though, which was my main point.

Comment: Re:Why ext4 (Score 1) 223

by Rich0 (#49744837) Attached to: Linux 4.0 Has a File-System Corruption Problem, RAID Users Warned

Why would you want to add just one drive to a server with 5x 6-drive RAID6 arrays? Just add another 6 drives at a time.

ZFS isn't ideal for growing like that since it doesn't do rebalancing. Your younger raid arrays will always have more data on them.
Also zfs destroy is very expensive.

Perhaps, but my point was more that if you want to grow ZFS this is the ONLY way to actually do it, as far as I'm aware. You can't add individual drives to individual "vdevs."

Comment: Re:Why ext4 (Score 2) 223

by Rich0 (#49743615) Attached to: Linux 4.0 Has a File-System Corruption Problem, RAID Users Warned

The problem is that the feature-list for ZFS is very enterprise-oriented.

Why would you want to add just one drive to a server with 5x 6-drive RAID6 arrays? Just add another 6 drives at a time.

On the other hand, if you have a PC with 3 drives in RAID5, you could easily want to turn that into a 4-drive RAID5 or a 5-drive RAID6 in-place.

Btrfs has a lot of features that are useful for smaller deployments, like being able to modify the equivalent of a vdev in-place. ZFS on the other hand has a lot of features like ZIL that are very useful for larger deployments.

Comment: Re:Plutonium Thermal-Electric? (Score 2) 116

by Rich0 (#49743527) Attached to: Hydrogen-Powered Drone Can Fly For 4 Hours at a Time

Agree. RTGs aren't actually all that efficient - they're a very primitive form of nuclear power. Their advantage is in their simplicity and longevity, which makes them great for things like spacecraft that need low power for VERY long duration, and where repairs are impossible.

You'd need a pretty big aircraft before nuclear turns into a viable option.

Comment: Just proprietary? (Score 4, Interesting) 125

by Rich0 (#49743431) Attached to: US Proposes Tighter Export Rules For Computer Security Tools

I'm interested in whether this is limited to ONLY proprietary research.

I could actually see an argument for banning export of such research. Do we really want companies finding flaws in widely-used software, keeping those flaws secret from the software vendors and the general public, but then selling details on those flaws to others who could potentially turn around and exploit them? In a sense, this does sound like a munition.

I don't see the same concern with public research. If you disclose a vulnerability publicly, then everybody can fix it, and that strengthens the ecosystem instead of weakening it.

If the ban were limited to proprietary research, I don't see it as a bad thing. Of course, it does nothing to keep companies from selling their findings to NSA contractors and such, but I don't expect the US to lift a finger to ban practices like these.

Comment: Re:Stupid (Score 1) 386

by Rich0 (#49743381) Attached to: Microsoft To Teachers: Using Pens and Paper Not Fair To Students

Diagramming on a whiteboard remotely is a different problem. It's easily solved by pointing the camera at the whiteboard behind you, at least when you have 3 different people in 2 locations. When you have 27 locations and 150 people on the call, what then? A shared whiteboard that everyone fucks up completely in the first 15 seconds because there is not enough whiteboard space?

In my experience the problem isn't getting everybody to not scribble on the board. The problem is that everybody has a 14" monitor and it is just really hard to do anything freehand on such a display. Maybe with graphics tablets and better software it might work.

Even diagramming something solo is a mess in my experience. I tend to end up doing mindmaps or outlines in Word or visio, but the last tends to be pretty painful to do quickly.

Comment: Re:Stupid (Score 1) 386

by Rich0 (#49743349) Attached to: Microsoft To Teachers: Using Pens and Paper Not Fair To Students

Depends on how badly your meetings are organized... no offense. If you structure them properly you can use whiteboards just fine. Works the same with power point. If you can't see the whiteboard than how can you see the power point?

The powerpoint is shared over webex, which is how everybody is connected to the meeting? :)

Comment: Re:Durability concerns valid, but... Tampering? (Score 2) 88

by Rich0 (#49727619) Attached to: Yubikey Neo Teardown and Durability Review

Not sure what benefit "tampering" would provide. Why would you have to take it apart to extract its secrets, when you can just: steal the person's smartphone/computer and the yubikey, and use them in tandem to authenticate yourself as the user to whatever services they have locked behind it? You can use the Yubikey all by itself, assuming you have exclusive physical access to the device, to make it serve its purpose for you, the attacker.

Sure, but you can ONLY use it while it is under your control if the embedded keys cannot be extracted.

If they can, then you can duplicate the key and return the original, perhaps undetected. That gives you the ability to retain access to whatever was secured.

There is definitely value in tamper-resistant key vaults.

Comment: Re:Selective prioitization (Score 4, Insightful) 221

There are so many ways that could be abused though - both by the ISPs and the end users.

Game server too laggy? Switch it to port 443 UDP - ISPs will think it's Skype voice and give it top priority.

There is a really simple solution to this. Allow users to set their own QoS rules, and the ISPs respect them, and can charge a different rate for different levels of service.

So, if you just want your SYNs prioritized it isn't a problem, and it probably won't cost you much. If you want your bittorrent traffic prioritized, that also isn't a problem, and it will cost you a fortune.

If everybody tried to ship all their mail/etc FedEx priority overnight FedEx would grind to a halt for months until they scaled up. It isn't a problem, and there are no limitations on what can be sent priority overnight, but people regulate themselves because most will not pay $70 to ship something when the $7 service that takes 2 days longer is good enough.

Comment: Re:Stupid (Score 1) 386

by Rich0 (#49727375) Attached to: Microsoft To Teachers: Using Pens and Paper Not Fair To Students

We have a couple of whiteboards that will spit out a printed copy of what is on them or send off a PDF of what is on them. Seems to work great.

That wouldn't work for a realtime meeting (think webex/etc). Also, if it only prints then you end up digitizing that and looking at it on a screen, which might or might not be readable.

One challenge with replacing whiteboards is just how much info you can present. If you're working close to it you could be writing on post-its/etc and it could be the equivalent of 30+pages of content on regular paper. Short of having ubiquitous 2m monitors I'm not sure if you'll ever completely replace them.

Comment: Re:Stupid (Score 1) 386

by Rich0 (#49725713) Attached to: Microsoft To Teachers: Using Pens and Paper Not Fair To Students

If you have an existing system that is as good as a more expensive electronic option then you would be foolish to replace the existing system.

Chalkboards and whiteboards are fine. They're entirely modern and you'll find them in use in modern business and modern academic settings at the HIGHEST level.

Yes and no. What I struggle with is the fact that most of the teams I work with are global in scale, and thus the whiteboard just doesn't work, and I've yet to find a really good alternative. Whiteboards also are not self-documenting. I've literally snapped photos of them with my cell phone and then I have to try to scroll around them on a tiny monitor (even on a PC).

I'm not sure whether Microsoft has a compelling solution to this problem, but I'm willing to buy into the argument that whiteboards are non-ideal in a lot of situations.

Now, in a traditional classroom with a teacher and 25 kids watching them lecture in a single room, I think the whiteboard works just fine. I do realize that is the focus of this discussion.

Comment: Re:Stupid (Score 1) 386

by Rich0 (#49725675) Attached to: Microsoft To Teachers: Using Pens and Paper Not Fair To Students

chalkboards and whiteboards are entirely reasonable in lectures and are still used in modern settings in business all the time.

TBH, whiteboards are pretty limiting in modern business settings these days. I love and hate them.

I love them because they really are the best medium for getting the job done.

I hate them because in a typical meeting only 10% of the participants can see the whiteboard, and we don't have many electronic alternatives that don't suck.

A good solution for students that actually works when viewed remotely would probably be something that would take off in the large business world.

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