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Comment Re:ZFS is nice... (Score 1) 173

No. RAID isn't better handled at other layers. If you don't know about the filesystem semantics then you need NVRAM or journalling at the block level to avoid the RAID-5 write hole. RAID-Z doesn't have this problem. If you're recovering a failed block-level RAID, then you need to copy all of the data, including unused space. With ZFS RAID (all levels), you only copy the used data. There are numerous other advantages to rearranging the layers, including being a lot more flexible in the provisioning.

It's also a mistake to think of ZFS as a layer. ZFS has three layers: the lowest handles physical disks and presents a linear address space, the middle presents a transactional object store, and the top presents something that looks like a filesystem (or a block device, which is useful for things like VM disk images).

Comment Re:ZFS is nice... (Score 1) 173

2GB/TB is recommended if you're doing deduplication. That said, performance degrades quite smoothly. I've got a machine with 3x4TB drives in RAID-Z with only 8GB of RAM. Disk performance isn't great, but I mostly access it via WiFi and it's absolutely fine for that. Eventually I'll get a new motherboard for that can handle more than 8GB of RAM...

Comment Re:Fukushima factoid - Thorium and Thallium (Score 1) 136

It's the gamma radiation that makes it less of a proliferation risk. Can't have detonators around that.

As for the radioactivity, yes, it's highly radioactive, but properly processed the waste is in said highly radioactive state for a substantially shorter period of time. Basically, it'll reach background levels in a period shorter than human civilization, not longer.

I'm fine with going with IFR, but I'm not sure what you mean by 'loose energy' (lose energy) for mining and processing Thorium - Thorium is currently a byproduct of rare earth mining and refining; currently they're avoiding some of the richest Thorium ore because there's no demand for thorium, thus it's expensive to handle the ore.

Start up a few thorium reactors such that there's a commercial demand for the metal, and it'll get mined along with the other stuff. One thing I've learned is that a 'pure' mine is actually pretty rare. Copper and gold mines also tend to produce silver. Rare earths are usually mixed. Etc...

Comment Re:Who? (Score 1) 581

You want some harsh criticism? And some direct, blunt communication?

People don't scare quote "hetero", because it's the antonym of "homo-". So why the hell are you scare quoting "cis-" when it's the antonym of "trans-"? This is basic Latin, and if you didn't take Latin, then it's basic Chem, and if you didn't take basic Chem, then GET OFF MY INTERNET.

Unless you're going to argue that transgendered/transsexual people don't exist, then stop scare quoting "cis-" like it's some sort of boogie word. It's the natural choice for referring to individuals who are not "trans-". And if "trans" is a word, then "cis" is a word. Just like "hetero" and "homo".

Don't like it? TOUGH! That's how language works.

Comment Re:We already had one (Score 4, Informative) 25

Yes, they're fictional, but it's a good start, since after all it proves that modern-day researchers weren't the first people to think of classifying planets by their habitability characteristics. Also, the simple "class [letter]" scheme is easy to remember and use; I sure hope they don't come up with some arcane, complicated system instead. Finally, they should definitely use "Class M" to refer to Earth-like planets simply to pay homage to Star Trek. Everyone and his brother knows what a "Class M" planet is, as long as they watched some Star Trek within the last 50 years.

It looks like you got your classes from Star Trek too, as seen here, but with some differences. I'm not sure where you got Class Q or I. The system probably does need a little revision though. Class H's "generally uninhabitable" doesn't tell you why. The Class P (see appendices) for icy planets is a good example. Class N for "sulphuric" really isn't sufficient; Venus is more like the Class Y "demon planet" except there's no dilithium-based biomimetic lifeforms, but the fact that Venus is so hot is important it needs to be classified that way. If a planet is too cold or too hot to live on, that's an important factor for humans. Same if there's no atmosphere. A planet (or moon) that's not too warm or hot but has no atmosphere can still be inhabited using domes or other sealed habitats, so that should be a class by itself. Mercury probably wouldn't fit there however, because it's much too hot. But it's hot in a different way than Venus, so they should have different classifications (hot because it's too close to the star, vs. hot because it has a thick atmosphere and runaway greenhouse effect). Finally, moons and planets should be classified together. The orbital path doesn't really matter (except insofar as it affects the climate/temperature). There could very well be Earth-like moons out there somewhere, so those should be Class M (like the moon in "Avatar").

So here's my proposal which borrows from ST:
Class M - Earth-like, small, rocky, oxygenated atmosphere, right temperature
Class D - small, rocky, little to no atmosphere, right temperature, inhabitable with sealed habitats (e.g. Mars)
Class J - gas giant (any size; this may be expanded later after we explore more star systems and decide we need to classify them further)
Class E - small, rocky, little to no atmosphere, too cold (e.g. Pluto)
Class F - small, rocky, little to no atmosphere, too hot (e.g. Mercury)
Class G - small, thick atmosphere, too hot (e.g. Venus)
Class A - very very small, not spherical (e.g. moons of Mars, captured asteroids)
Class B - very small, spherical but extremely low gravity (e.g. Sedna, Ceres, Pluto, dwarf planets in general)

I'm probably missing something here, perhaps planets with only liquid surfaces. I avoided calling Venus "Class N" because it sounds too much like "Class M".

Comment Re:BTRFS is getting there (Score 1) 173

I don't why so many in the Linux community are so hooked on ZFS. BTRFS has a feature set that is rapidly getting there,

I think you already explained it in that first sentence... ZFS has been stable, reliable, and successfully managing huge amounts of data for the past decade (2005). BTRFS is still unstable, not remotely a suitable alternative for ZFS, with only the vague promise of maybe eventually "getting there".

Comment Re:Not surprising (Score 1) 315

Well, unless you count App Ops in Android 4.3 (until it was removed) and builds of CyanogenMod starting with 10.2.

Or any Android device with 4.3 or later with the Xposed framework and the AppOpsXposed module installed and active, at which point AppOps shows up in Settings just like it ought to.

Comment Re:Not surprising (Score 1) 315

And in my experience, apps don't seem to much care if you kill a flag or two. Perhaps because the ability to do so is not yet that common.

There are multiple reasons. Mostly two: you don't want to fail if the user is missing some hardware that the software can work without, and the app doesn't actually request the permission from the OS until it wants to use it, unless it's very poorly designed. So if you for example deny the microphone permission, the app will never even have to decide if it's upset about that unless it tries to grab some audio.

I forget what versions it appeared and disappeared, but Google did put this functionality into an older version of android, then removed it again. You can get it back on rooted devices by installing Xposed and installing AppOppsXposed. Many custom ROMs also have this functionality baked into the ROM so you don't need to mess with Xposed, but Xposed+App Settings+Gravitybox is very wonderful and you want it anyway, if you're not running CM especially. If you can't root your device, make better purchase decisions in the future.

Comment Re:ZFS is nice... (Score 1) 173

I don't have a serial terminal, so having video output when needed is very important

So that's three-strikes... You're 1) using a regular PC as a server (no IPMI), 2) that PC doesn't even have a serial port to be used as an OoBM console, and finally 3) you've got some issue with the video card not even displaying text-mode. With all three strikes against your server, I just can't muster any sympathy for the predicament you put yourself in, relying on an unsuitable cheap piece of crap equipment.

In fact it's probably FOUR strikes... Presumably your video problem was an issue with KMS or similar, and 4) you didn't bother to figure out how to fix/disable/bypass it, and use plan old text-mode. Instead you went with the quickest (but obviously flawed and easily breakable) option of depending on a proprietary video driver. That's just not thinking things through. Reminds me of folks who has just a switchable PDU as their sole method of OoBM... works right up until they acidentally do a clean shutdown of a remote server.

Comment Re:Documentation is rarely valued as a contributio (Score 1) 391

Unfortunately, this shows why books are kinda obsolete for anything that's still under development. For things like awk, sed, grep, etc., they're great, because those things haven't changed much in ages. For a whole OS, not so much; they're all changing constantly. There is an e-book on git at, but being an e-book it gets updated, plus it seems like git has stabilized now.

I'm not so sure the cathedral model is really necessary for a competent and motivated tech writer however. As long as the tech writer can navigate git (using a GUI program like gitk or TortoiseGit or whatever), they can follow the development of the project and then update the documentation soon after changes are made, having the doc updates ready in time for major releases.

But for anything that's still under active development, the docs are always going to be going out-of-date unless someone keeps them up-to-date. This is true of any software project. You can't use a book about Windows Vista for Windows 10.

Comment Re:ZFS is nice... (Score 1) 173

And even then, IPMI is extremely limited.

I don't see how anyone can claim "IPMI is extremely limited" with a straight face. It does nearly everything you could want in an OoBM interface, except (usually) a GUI. You can do lights-out management, powering systems off and on, setting BIOS/UEFI options like boot device statelessly (not just at boot-up), it can be configured to have a dedicated NIC port, or shared with the OS whether you're bonding NICs or not, gives you a serial console (including BIOS access) over the network. etc., etc.

Comment Re:ZFS is nice... (Score 1) 173

And IPMI console typically requires java. Within a year or so NO browser will support that!

No, you can use serial-over-LAN via native utilities like ipmitool. You're talking about the idiot-friendly web interface a few OEMs happen to include. Most ipmi implementations don't even have any web/browser interface to begin with.

"We shall reach greater and greater platitudes of achievement." -- Richard J. Daley