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Ext4 Filesystem Enters Experimental Kernel Tree
An anonymous reader writes "Looks like the next version of the venerable Linux 'ext' filesystem is just around the corner. Andrew Morton has added an early version of ext4 to his 2.6.19-rc1-mm1 tree, enabling Linux to support storage volumes up to 1020 petabytes in size, and to write files in 'extents,' or contiguous, reserved areas. According to an article at Linux-Watch, ext4 will be ready for production use within six to nine months, if all goes well. On the downside, the new ext4 filesystem will offer only limited backward compatibility with ext3-aware Linux kernels."
1 Exabyte!
Not to be confused with Excitebike, which is something entirely different.
The Slashdot Paradox: "100% Overrated"
EXT4-fs warning (device sdb1): ext4_journal_start_sb: Detected tasteless ReiserFS jokes - hahahaha!
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By now you don't even now what to do with 1024PB. Just as we couldn't imagine filling a 250GB harddrive 15 years ago when 500MB were considered huge.
What will happen? We store our digital photos in raw format, not JPEG. We store our songs in raw format, not artificially crippled. We will store high-definition video, possibly even in raw format, not MPEG4 or the likes.
And, woosh, 1024PB will be nothing leaving us wondering how we could ever survive with a measly 250GB drive -- just as we ask ourselves today how life was with nothing but 170kB disk drives.
How does ext4 perform when compared to, say, reiserfs 3.6 or 4? What new features there are?
Who is John Galt?
My question is why they don't mention why it is better to use ext4 then XFS.
XFS can do 9 exabytes (exabyte = 1024 petabytes).
They mention that ext4 is not faster than other filesystems.
Ofcourse people can do whatever they want, but why not spend their time making XFS easily resizable for example?
If you mod this up, your slashdot background will turn into a beautiful sunset!
Will we back all this data up?
I'm honestly more interested in someone coming up with cheap, long term archival storage. Hard disks have gone so far past our ability to archive information it's beyond comprehension.
Clear, Dark Skies
Well, that depends on what your expectations for the future are. I don't think it is impossible that demands on multimedia will reach high enough sometime. Let us as an example consider a movie file from the Future (tm). Given better and bigger screens (perhaps covering whole walls) a frame dimension of 3000 x 2000 pixels is not inconceivable. Each pixel might consist of three RGB values of 16 bits each. Such a movie, if two hours long and running with 25 frames / second, would require about 6.5 TB in raw format.
framedimensions = 3000 x 2000
framebytes = framedimensions x 6
moviebytes = framebytes x 25 x 60 x 120
moviebytes / 10^12 ~= 6.5
to no longer use ReiserFS as its default FS (orig. reported on OSNews.com...don't think I've seen it here yet). I think this came out before the whole Hans Reiser affair, BTW.
SuSE contrasted the ease of upgrading ReiserFS and ExtFS versions:
Carousel is a lie!
>> 1020 petabytes
My porn collection will now be complete.
Liar... there is no such thing as a complete porn collection!
So say we all
The limits are set by our senses, more concretely, our ears and our eyes.
Our ears are only capable of hearing up to about 20Khz (less than that for most people) and 16-bit samplings are enough that most people cannot hear the difference with anything more. Thus CD-quality is, if not perfect, then good enough that further improvements are ignorable for most people. CD-quality losslessly-compressed music is around 300MB/hour.
In a year, there's 8760 hours, so you'd need on the order of 2.5 TB to store a year worth of around-the-clock never-repeateing losslessly-compressed music. If computers keep getting replaced at the current rate, this means you'll never need more than about 10TB to store sound. This assumes you don't store more than you listen to, if you choose to for example store all music ever produced for convenience, despite never listening to more than a tiny fraction of it, then this requirement goes up by a couple of orders of magnitude. Still, there's good reason to suppose that 10TB will suffice for most peoples sound-storage needs. (even if you wanted to store all the sound you've *ever* heard in your life, including traffic at nigth, that'd still only be 200TB or so)
The real killer is video. We can take in a *lot* more data with our eyes. 10GB/hour is in the ballpark of what you'd need for the sort of quality a modern cinema can deliver. (and there's no particular reason we couldn't go higher.) That works out to 100TB/year, more or less. A lifetime of high-quality video is thus on the order of 10PB.
In short, it is unlikely that an individual (or family) will be able to fill a 1000PB disc with sound and video-recordings. Infact it's unlikely they'll be able to fill it with anything, if that anything is to be consumed only trough their 2 eyes and 2 ears.
That doesn't mean it won't happen. Only that it'll be filled with something more. Once we fire up the holodecks all bets are off. I don't even want to try to estimate the bandwith needed for that kind of immersive experience.
As much as I agree with you questioning the many 'funny' ACs, I can't support this statement. One day you, yes, you, might also become a suspect. And then, suddenly, you would see the world with different eyes. Especially, when you're found innocent and you also find that your friends have deleted all memories of you since they don't want to be associated with you; as suspect.
I am sure many of us would feel similar once the investigation is over and Hans eventually found guilty. But as civilised people, we better wait. How old are you ? Have you never ever been suspected of something ?