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133 comments

Stable? (5, Informative)

Anonymous Coward | about 7 months ago | (#45757087)

"LTS is an abbreviation for "Long Term Support" [ubuntu.com] ."

WHAT THE FUCK ARE YOU DOING?! (5, Funny)

Anonymous Coward | about 7 months ago | (#45757163)

HOLY FUCK, MAN! JUST WHAT THE HELL DO YOU THINK YOU'RE DOING?!?!?!

This is Slashdot, for crying out loud. How DARE you bring facts and correct information to the discussion here! THAT IS NOT ALLOWED! You just can't do that! FUCK!

Re:WHAT THE FUCK ARE YOU DOING?! (2)

voss (52565) | about 7 months ago | (#45757545)

I wish I had a +1 funny mod point for him

Re:WHAT THE FUCK ARE YOU DOING?! (1)

johnnys (592333) | about 7 months ago | (#45757611)

What he said!!

Re:WHAT THE FUCK ARE YOU DOING?! (1)

lexman098 (1983842) | about 7 months ago | (#45757805)

You don't waste mod points on an AC

Re:WHAT THE FUCK ARE YOU DOING?! (2, Informative)

Anonymous Coward | about 7 months ago | (#45759033)

You don't waste mod points on an AC

Mod up good ideas. The name (or lack therof) is irrelevant.

I say, Welcome to this Decade already! (0)

Anonymous Coward | about 7 months ago | (#45757091)

We were wondering ... not!

It's Long-term support... (1)

Anonymous Coward | about 7 months ago | (#45757103)

Aside from this being old news, along with the typical comments about Windows 7 having the feature since introduction.

Re:It's Long-term support... (2, Informative)

Anonymous Coward | about 7 months ago | (#45757133)

along with the typical comments about Windows 7 having the feature since introduction

Well, let me be that guy... ;)

Windows implements TRIM command for more than just file delete operations. The TRIM operation is fully integrated with partition- and volume-level commands like format and delete, with file system commands relating to truncate and compression, and with the Volume Snapshot feature.[1] [msdn.com]

Re:It's Long-term support... (0)

fisted (2295862) | about 7 months ago | (#45757741)

Cool, so they're only how many years behind?

Re:It's Long-term support... (0)

Anonymous Coward | about 7 months ago | (#45757807)

It sounds like Linux is four years behind.

Ubuntu != Linux (4, Informative)

Anonymous Coward | about 7 months ago | (#45758615)

It's been in the kernel for a long time now, google tells me since 2.6.33 (Which was released early 2010, about a half a year after Windows 7 was released). Ubuntu 12.04 (The last LTS) shipped with 3.2, so you could already enable TRIM using 12.04. This announcement is nothing more then a default settings change, I have no idea why it's even a big deal (Or why this wasn't already the default, I've been using it for a while now).

"Good news for hardware enthusiasts!"... (0)

Anonymous Coward | about 7 months ago | (#45757113)

or anyone with a SSD!

Re: "Good news for hardware enthusiasts!"... (0)

Anonymous Coward | about 7 months ago | (#45757129)

No kidding. All I use in systems I build now are SSDs. Even low end. Most people don't need all that space to hoard files and would rather have the performance.

So you build gamer boxes (0)

Anonymous Coward | about 7 months ago | (#45757489)

So you build gamer boxes then. I imagine sales have tanked pretty good of late.

Re: "Good news for hardware enthusiasts!"... (0)

Anonymous Coward | about 7 months ago | (#45757501)

No one I know, that's not a gamer or developer, uses a desktop anymore.

Re: "Good news for hardware enthusiasts!"... (4, Insightful)

Gadget_Guy (627405) | about 7 months ago | (#45757575)

...or typesetters & typists, accountants, video editors, music composers, engineers & architects, etc. In fact, anyone who produces, rather than consumes will tend to use computers as their main system. SSDs work nicely for all of them, if only to store the OS and program files.

That you only know gamers and developers says more about the company you keep rather than what technology is used out there. It is true that tablets and smart phone sales are on the rise and PC sales are declining, but that doesn't mean that people have stopped using their old computers.

Re: "Good news for hardware enthusiasts!"... (1)

Anonymous Coward | about 7 months ago | (#45758115)

I'm still using a dual socket quad core Xeon from 2006. Plenty of speed. Not sure when I will need more. I have a second desktop that is a 2700k. Just as fast. Only upgrades I do are ssds or 4tb drives. I will run these until they just stop. 5 more years, maybe 10... Whatever.

Re: "Good news for hardware enthusiasts!" (1)

TheGrimmReaper (1927686) | about 7 months ago | (#45757579)

What does desktop vs. laptop have to do with it? Plenty of people use SSD's in desktops (I sure do)

Defeats pleasure of unnecessary labour (4, Funny)

Twinbee (767046) | about 7 months ago | (#45757125)

But surely this defeats the perceived satisfaction of tweaking and fixing it all up manually? Where's the fun in that?

Re:Defeats pleasure of unnecessary labour (4, Interesting)

TeknoHog (164938) | about 7 months ago | (#45757179)

But surely this defeats the perceived satisfaction of tweaking and fixing it all up manually? Where's the fun in that?

If that's your thing, use Gentoo instead. At least that's what I do. In case you're being sarcastic, the fun IMHO is in learning about your system and understanding why distros make the choices they do. I think my first week with Linux taught me more about computers than years with DOS/Windows, and I still wonder how a Windows machine can be anyone's "Personal Computer".

Re:Defeats pleasure of unnecessary labour (0)

Anonymous Coward | about 7 months ago | (#45757743)

Gentoo is fine if you're a sadist, but the rest of us will stick with Slackware. And then there's this [youtube.com] and this [youtube.com]

Re:Defeats pleasure of unnecessary labour (1)

jones_supa (887896) | about 7 months ago | (#45757815)

What are "this" and "this"?

Re:Defeats pleasure of unnecessary labour (-1)

Anonymous Coward | about 7 months ago | (#45757967)

Burn in hell, anime pedo.

Re:Defeats pleasure of unnecessary labour (0)

Anonymous Coward | about 7 months ago | (#45758473)

> If that's your thing, use Gentoo instead. A

I'm sorry, I have a day job....

Re:Defeats pleasure of unnecessary labour (0, Insightful)

Anonymous Coward | about 7 months ago | (#45758621)

I strongly disagree. I found my first week with Linux, and subsequent weeks prodding it to make it work like I wanted it to was all about learning how Linux worked, and not much about computers. For example, I needed to learn how to edit the xorg.conf file so I could implement the side buttons on my Logitech mouse at the time (so you can browse back/foward in web sites and file managers without having to move the mouse). In Windows it was bloody easy - it WORKED, even without any special Logitech drivers. In Linux the side buttons didn't do shit until I configured xorg.conf to understand what kind of mouse I had.

That episode was a good introduction to the problems that occur when going off the beaten track and trying to be "special" (i.e. use Linux on the desktop instead of a incredibly widely supported system like Windows). It's better nowadays - much better in fact. But learning about computers through Linux? Hell no.

Your other fun (2)

tepples (727027) | about 7 months ago | (#45757199)

The fun in having a distribution automatically do the right thing is that you get to a working system faster, so that you can get to your other fun faster, whether you prefer casual, hardcore, or Dwarf Fortress [imgur.com] .

Taking too long (5, Insightful)

Anonymous Coward | about 7 months ago | (#45757139)

This is way overdue.

It's also taking too long for file systems that provide snapshot features to become mainstream and default as well. And no, LVM snapshots aren't good enough.

No, I'm not going to write the patches. They wouldn't be accepted in any case. Fundamental features such as the IO stack and file systems are now the exclusive purview of well-heeled outfits like Red Hat, Oracle, Intel, OSDL, etc. and and their stable of full time developers.

They just need to do their jobs and get it done.

Re:Taking too long (1)

csirac (574795) | about 7 months ago | (#45757401)

I've been choosing btrfs through the debian installer for at least a couple of years now. Yes, I know it's not as awesome as ZFS, but it still beats mdraid and lvm.

Re:Taking too long (5, Funny)

darkpixel2k (623900) | about 7 months ago | (#45758203)

I've been choosing btrfs through the debian installer for at least a couple of years now.

Dude you so have to try ZFS. It's aweso--

Yes, I know it's not as awesome as ZFS, but it still beats mdraid and lvm.

Oh--sorry. Got ahead of myself there. Good thing you stopped me in time.

Re:Taking too long (0)

Anonymous Coward | about 7 months ago | (#45758507)

Neither mdraid nor lvm are actually filesystems. They're a middle layer in between your disk and your filesystem, to provide an abstraction layer between your disk and your filesystem, to allow aggregation and segregation of the hardware in ways that would require expensive hardware resources to manage. Unfortunately, I'm afraid that many systems personnel have lost site of the fact that both are _pointless_ in virtualized environments, and have no use there where the hardware layer has already been abstracted. It's been incredibly amusing to watch colleagues burning time, and wasting CPU and systems resources, trying to interject additional layers of abstraction in such environments when there's simply no need. Stick to raw disk images for virtualized environments, and throw out mdadm and LVM entirely for virtual guests.

ZFS and btrfs are a very different toolkits, but are far more useful at the virtual server layer. There is just no point to them in the virtual guest environments unless you want spend CPU cycles pointlessly.

Re:Taking too long (1)

profplump (309017) | about 7 months ago | (#45757483)

I'm currently using LVM snapshots for upgrades and backups -- what am I missing compared file system snapshots?

Why? (0)

Anonymous Coward | about 7 months ago | (#45757145)

Why is this "good news for hardware enthusiasts"? If you are a hardware enthusiast and running linux I don't think you really even mind or care about adding one word to fstab.

Done for a while (0)

Anonymous Coward | about 7 months ago | (#45758509)

I had a disk die a few years ago, and replaced it with an SSD. The guy in the store was a windblows guy: "Too bad Linux doesn't support trim". I bought the SSD, and ...Linux has been supporting trim for years. I add discard when installing new systems. It would be nice out of the box, but it only takes about 30 seconds to add the word 'trim' to fstab. I also get new microcode from Intel and get it loading in /etc/init.d/rc.local. Again, its a 30 second thing that brings the processor up to date. I don't know why the windblows people are yelping that 'Linux is behind' when it comes to file systems. I've been using Linux since 1994, and all my file systems have been self cleaning. I remember seeing hundreds of forums even up to the early 2000's windows users telling each other to 'remember to defrag your hard drive'. WTF? Didn't IBM create self-cleaning file systems in 1967? Linux has had it since (at least) 1994, the windblows folk (apparently) got it sometime after 2000.

TRIM not always good (5, Interesting)

girlintraining (1395911) | about 7 months ago | (#45757185)

the new LTS (Long Term Stable) version of Ubuntu Linux will automatically enable TRIM for your SSD. Good news for hardware enthusiasts!"

And terrible news for encryption experts. Enabling TRIM tells your adversary which sectors contain data and which don't. It's a great asset to cryptanalysis and also destroys plausible deniability that there's a filesystem present on the drive, and how much data is present in it -- thus eliminating the "shadow volume" option of Truecrypt and others.

Re:TRIM not always good (0, Troll)

BitZtream (692029) | about 7 months ago | (#45757223)

... Enabling TRIM tells them which sectors HAD data in them.

So unless you can magically teleport the drive from its location, away from its internal super capacitors designed to ensure unexpected power interruptions aren't a problem .. BEFORE the drive has a chance to act on the trim commands ... then MAYBE you can get SOME data.

After the drive gets the TRIM command in its buffer, you're SOL. It will most certainly be deleted before you get to it.

More importantly, if someone is somehow managing to get access to the data about which sectors are being TRIMd .... they've already rooted your machine and have complete control over it, since you know, thats data that only the kernel has access to.

So basically, the comment you probably thought was incredibly clever ... is just 100% ignorant of reality.

There is pretty much nothing in your statement that is true. You don't understand how shadow volumes work. You're making up silly scenarios that don't exist for SSDs or HDDs.

You need more training.

Re:TRIM not always good (5, Interesting)

Anonymous Coward | about 7 months ago | (#45757385)

No, YOU clearly don't know what you're talking about, and yet are arrogant as all hell.
The problem arises from the fact that while HDDs have only 2 operations (read, write) and therefore have no distinction outside the file-system of what is "free" and what is "allocated", SSDs have 3 (read, write, free), because SSDs label sectors as "free" or "allocated" (that is, the hardware itself, not just the file-system). So for a standard HDD encryption, the procedure goes: overwrite hard drive with random data, create encrypted partition, install OS on encrypted partition (last step optional, of course). What this accomplishes is that an attacker who examines the disk can't tell the difference between what is and isn't written to, since the unwritten data is random and the written data is encrypted (i.e. indistinguishable from random, if done correctly). On a TRIM-enabled SSD though, the OS sees all these unused sectors and proceeds to mark them as Free. That is a huge fucking problem, for the roughly the reasons the GP stated. In particular, it's egregiously bad for users of hidden volumes, since that hidden volume will never be TRIMed, and the attacker who can rubber hose your outer volume can see a chunk of disk that hasn't been trimmed, yet isn't allocated in the partition you gave them. They can now rubber hose THAT partition as well, whereas previously there was no way to know it even existed (in theory at least, the cryptsetup guys don't buy that).

If you don't believe this is an issue, then ask the Truecrypt devs:
http://www.truecrypt.org/docs/trim-operation

or the LUKS/dm-crypt devs:
http://asalor.blogspot.com/2011/08/trim-dm-crypt-problems.html

Please be more respectful in the future, as we're wrong more often than we like to think.

Re:TRIM not always good (3, Funny)

Anonymous Coward | about 7 months ago | (#45757529)

He can't be wrong though, he's already marked at Score 4: Insightful at the time of this post. And since Slashdotters are so smart and intelligent the score must be correct, right?

I dunno. Problem is it's hard to know who's right and who's not. All I know is that Windows 7 had TRIM support automatically enabled for SSDs back in 2009 and the leading Linux distro's only finally going to enable it in 2014. No wonder so many people still see Linux as old and not suitable for end-user machines.

Re:TRIM not always good (-1, Offtopic)

girlintraining (1395911) | about 7 months ago | (#45757563)

Please be more respectful in the future, as we're wrong more often than we like to think.

He wasn't being disrespectful because he thought my post was technically inaccurate, he was being disrespectful because a lot of people don't like me on slashdot because I have strong opinions and mercilessly club their favorite things, which they feel deserve special treatment. Whether it's mac, linux, windows, open source, copyright, left, right, obama, palin, tea partier, communist, and the list goes on... any opinion I state winds up pissing off some fanboy. That's why I put it as my tagline --

Not only do people downmod me for telling them their favorite band sucks, but they also upmod people who put down the evil heretic that is me. That's the only reason this guy got any points: It's GIT hate mail and a lot of lurker mods just eat it up.

Re:TRIM not always good (-1)

Anonymous Coward | about 7 months ago | (#45757669)

Please be more respectful in the future, as we're wrong more often than we like to think.

He wasn't being disrespectful because he thought my post was technically inaccurate, he was being disrespectful because a lot of people don't like me on slashdot because I have strong opinions and mercilessly club their favorite things, which they feel deserve special treatment. Whether it's mac, linux, windows, open source, copyright, left, right, obama, palin, tea partier, communist, and the list goes on... any opinion I state winds up pissing off some fanboy. That's why I put it as my tagline --

Not only do people downmod me for telling them their favorite band sucks, but they also upmod people who put down the evil heretic that is me. That's the only reason this guy got any points: It's GIT hate mail and a lot of lurker mods just eat it up.

I like your style - now go and mercilessly club the left-wing nigger lover faggets army of /.

Re:TRIM not always good (0)

infinitelink (963279) | about 7 months ago | (#45757671)

He wasn't being disrespectful because he thought my post was technically inaccurate, he was being disrespectful because a lot of people don't like me on slashdot because I have strong opinions and mercilessly club their favorite things

xD I enjoy your bitchiness, but I'm a wackjob. ;) Keep it up.

Regards.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45757717)

I modded you down right now, because I hate off-topic posts and stupid drama, not because I hate you (well, I dont hate you either).

Re:TRIM not always good (-1)

Anonymous Coward | about 7 months ago | (#45757759)

No, you're just a dickhead. Nothing special, nothing useful. An irritating nothing.

Re:TRIM not always good (1)

Jherek Carnelian (831679) | about 7 months ago | (#45757785)

any opinion I state winds up pissing off some fanboy.

And the best thing about your posts is that they are never wrong!
Narcissism FTW!

Re:TRIM not always good (3, Insightful)

fisted (2295862) | about 7 months ago | (#45757817)

Wow you seem to be one egocentric person.

Re: TRIM not always good (1)

Anonymous Coward | about 7 months ago | (#45758227)

Um, you should get over yourself.

Re:TRIM not always good (1)

VortexCortex (1117377) | about 7 months ago | (#45757747)

I agree and would only like to add that on magnetic media you should use a low level disk maintenance program periodically to reads and writes blocks in place, thus refreshing the signature of the drive. Otherwise I can tell from the error correction frequency of the rotting magnetic bits that you have a "hidden" volume. SSD / flash drives had a similar problem before ware-leveling was common.

Re:TRIM not always good (1)

LordLimecat (1103839) | about 7 months ago | (#45758445)

You could, I dont know, check the size of the partition on the "plausible" volume he shows you. If drive size is 500GB, and the "plausible" partition is 250, and hes using truecrypt... GEE I WONDER.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45758779)

The outer parttition could be all 500GB and the hidden partition could still be 250GB. The relationship between hidden and outer is that of nested partitions, not contiguous partitions. The hidden partition is stored in the slackspace of the filesystem, not the drive.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45758069)

SSDs and whole disk encryption are certainly an issue. For WDE to work well you need to make an entire partition opaque to outside attackers, so you can't have obviously free sectors on it, lest you narrow the search space for relevant data.

At any rate, the simplest solution would seem to be for the file system to only trim a certain amount, say perhaps 8GB out of 256GB and leave the rest marked as filled, even when it technically isn't, to preserve as much as possible of the benefits of encryption, while allowing the potential of faster writes. Of course even the pattern of the space that is trimmed might have some value, so care might be required there when considering how to go about it.

I remember reading at one point the suggestion to leave free space on an SSD with WDE to do the same thing, but I'm not sure that quite works, since how is the drive supposed to know which blocks can be swapped between the partition and the free space if it has no knowledge of the encryption..?

Re:TRIM not always good (5, Insightful)

LordLimecat (1103839) | about 7 months ago | (#45758439)

Dude, youre overstating the threat.

If the drive is encrypted, theres no more or less threat from brute-forcing.

From a plausible deniability standpoint, Im not terribly sure how helpful that is ANYWAYS. If someone wants to know if youre using truecrypt, they could, I dont know, look at the MBR and see whether its using the Truecrypt bootloader. The idea that you can say "What partition?" when goons grab your mysteriously unreadable laptop is laughable. Im sure there are super corner cases where that would be helpful, but generally if youre being held by the sorts of people who have the means and ability to do rubber hose cryptography, theyre not going to put up with your BS about "but wait look i gave you a password that boots to an Ubuntu partition which only accounts for 1/2 of the drive's size, and has no data worth encrypting whatsoever!"

Being involved with multiple organizations which employ encryption for very different reasons, none of them use plausible deniability / hidden encryptions; Id reckon because its not terribly helpful, or even plausible.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45758775)

If the drive is encrypted, theres no more or less threat from brute-forcing.

Brute-focring? That threat model never changes, that's why the standard of "broken crypto" is an attack more efficient than bruteforcing. So of course there's no more or less threat from it. However, if you're saying that this doesn't make your data any more or less secure, you're wrong about that. If you read the links I provided, they detail how this provides a means of finding leaked data, such as the filesystem you're using. This could be useful for known plaintext attacks (of which there really aren't any for AES afaik, but saying that this doesn't weaken the security is plain wrong). There's also (as of now unpublished, afaik) reasearch I know of where you can use where (and when, depending on the attack) data was written to disk to narrow down the possible contents. It's pretty well established that any leak of information is bad news, cryptographically.

From a plausible deniability standpoint, Im not terribly sure how helpful that is ANYWAYS.

Like I said, niether are the cryptsetup team, that's why they don't provide support for creating hidden volumes.

If someone wants to know if youre using truecrypt, they could, I dont know, look at the MBR and see whether its using the Truecrypt bootloader. The idea that you can say "What partition?" when goons grab your mysteriously unreadable laptop is laughable.

I don't think you understand hidden volumes. The idea is that there's an outer encrypted volume, which you disclose, and then hidden in the slack space of that volume, another encrypted volume exists. The point of that being, when coersive measures are in play, only the outer volume is divulged. There is nothing particularly special about the slack space of the hidden volume, it looks just like actual unused space interspersed with the used space on a used volume (this is where the cryptsetup team disagrees, as the method TC uses to accomplish this is... less than graceful).

Im sure there are super corner cases where that would be helpful, but generally if youre being held by the sorts of people who have the means and ability to do rubber hose cryptography, theyre not going to put up with your BS about "but wait look i gave you a password that boots to an Ubuntu partition which only accounts for 1/2 of the drive's size, and has no data worth encrypting whatsoever!"

Now this leads me to believe you do understand, despite the fact it directly contradicts your earlier statement. In any case: Hidden volumes are supposed to provide plausible deniability, the key word there being plausible. If you see someone with a half full hard drive, your first thought isn't "there's a hidden volume." My primary drive is far, far less than half full (I use a dedicated SSD for my root partition, wheras most of my actual data is stored in my /home drive). Can a coersive actor continue to use rubber hose methods to force you to divulge a hidden partition? I suppose, but they sure as hell can't in any jurisdiction where "innocent until proven guilty" still has any say, and they'd basically end up torturing me to death I guess.

Being involved with multiple organizations which employ encryption for very different reasons, none of them use plausible deniability / hidden encryptions; Id reckon because its not terribly helpful, or even plausible.

Then your threat model is clearly different from those who do need it, so I'm not sure how that applies then. For example, if Greenwald's partner had a hidden volume on the siezed drive (and it's entirely possible he did), it easily could have bought him the time needed to force his detaining into the maximum time limit.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45757749)

That is girlintraining's MO. Constantly spouting nonsense on topics he doesn't understand, then starting flamewars when people correct him.

It is best to just ignore him.

Re:TRIM not always good (1)

Khyber (864651) | about 7 months ago | (#45757927)

"You need more training."

Speak for yourself, failure at cryptoanalysis.

That's how I break into encrypted crap all the time. SSDs make it much easier to find hidden data.

Re:TRIM not always good (1)

darkpixel2k (623900) | about 7 months ago | (#45758211)

That's how I break into encrypted crap all the time.

The new locks your mom put on the basement door don't count.

Re:TRIM not always good (1)

Khyber (864651) | about 7 months ago | (#45758323)

Trying to insult tends to fall flat when I'm one of the people responsible for your low food prices.

It's your mother living in my basement, child. She services my husband and myself.

Re:TRIM not always good (1)

darkpixel2k (623900) | about 7 months ago | (#45758339)

Trying to insult tends to fall flat when I'm one of the people responsible for your low food prices.

Eh? Who are you and how are you responsible for decreasing the price of the food I grow on my farm?

Re:TRIM not always good (1)

Anonymous Coward | about 7 months ago | (#45757239)

Hmm? trimmed-sectors return all zeroes. Non-written sectors also return all zeroes. SSDs are not exactly well-tailored for encripted volume usage, and that's it.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45757449)

Wrong.
There's 2 ATA feature flags concerning read-after-trim behavior.
Read Zero after Trim
and
Deterministic Read After Trim

If your SSD doesn't have Read Zero after Trim, it's perfectly free to return the previous data or completely random junk when reading a TRIMed block (note: it *can* return zeros, but it doesn't have to).
If it doesn't have Deterministic Read After Trim, it can even return different data for successive reads of the same TRIMed block (e.g. you TRIM a block, read it, get the original data, read it again, get random junk, read it again, get zeros).

Re:TRIM not always good (1)

Billly Gates (198444) | about 7 months ago | (#45757315)

Oh please.

Most users don't want their drives go down to 5 megs per second. Trying to justify your OS doesn't cut it.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45757437)

This is only at the filesystem layer - it won't go through to the block device if the dm-crypt layer doesn't have "allow-discards"

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45757595)

Plausible Deniability is bullshit anyway and is just schuck-bait that can have your Mr. Dissident end up diappearing in a torture dungeon because EVERYBODY knows that truecrypt supports those hidden volumes and he has no way to proof that he isn't hiding anymore even if he gives them the main password.

Re:TRIM not always good (1)

lilrobbie (1193045) | about 7 months ago | (#45758207)

Isn't this one of those situations though where if you are likely to be rubber-hosed, you probably would have compiled the kernel yourself with this type of thing disabled?

I can't see someone downloading and installing a pre-compiled distro if they are that worried about security....

Re:TRIM not always good (1)

at_slashdot (674436) | about 7 months ago | (#45758419)

Isn't that a configuration that can be changed? That's a default, I assume the "experts" will have no problem to set up their desired behavior.

Re:TRIM not always good (0)

Anonymous Coward | about 7 months ago | (#45758449)

I see your point. Can this 'feature' be turned off? Even if it can, someone is still tipped off that your unused sectors may not be so unused after all I suppose.

Re:TRIM not always good (2)

craighansen (744648) | about 7 months ago | (#45758499)

(1) [Easiest solution] Turn off TRIM usage on encrypted volumes - loss of peak performance, but now you've got your "plausable deniability" back

(2) [Adequate solution] Fix the firmware so that reading a TRIMed block causes random data to be written to it. However, you had better make sure that exactly the same power usage and timing comes from this activity compared to reading a previously-written block. You had also better be sure that the data is really random, so it can't be distinguished from encrypted data. You must also protect the meta-information as to the number of free and erased blocks.

(3) [Problematic solution] Do not attempt to simply return psuedo-random data for blocks that have been TRIMed - you must ensure both that additional reads return the same data (such as by seeding the PR generator with the block number) and that performing additional TRIMs on the block cause different data to be returned, so that the ruse cannot be detected by reading the block, performing a TRIM, and reading the block again to see if it's the same. This is actually difficult, as any finite amount of state representing the seed could be detected by multiple TRIM/read cycles, although the effort required grows exponentially with the amount of state used.

Re:TRIM not always good (1)

SlashRAH (1236462) | about 7 months ago | (#45759001)

By default, LUKS ignores (errors, actually) those discard/TRIM messages at the block device layer, preventing the SSD from processing them. You have to explicitly override this in order to TRIM a block device under an encrypted filesystem, in which case you're on your own.

The Crumbling Kingdom of Buntu (-1)

Anonymous Coward | about 7 months ago | (#45757193)

All the past and present grumbling about Ubuntu, Unity, and spyware is a waste of time and resources.

Download a minimal Debian iso and install/build from there. Google[1] for 'Debian minimal install'. I no longer recommend or use (K)(X)(L)(U)(whatever)buntu. Fool me once, never again. I urge you to switch from Ubuntu to a distro you are comfortable with, and one which doesn't draw from Ubuntu's package repositories.

[1] or use ixquick, startpage, duckduckgo search engines

Re:The Crumbling Kingdom of Buntu (-1)

Anonymous Coward | about 7 months ago | (#45757215)

Pok pok pok, P'kok!

Re:The Crumbling Kingdom of Buntu (1)

fisted (2295862) | about 7 months ago | (#45757849)

Why is this modded down? It isn't even bad advice.

Re:The Crumbling Kingdom of Buntu (0)

Anonymous Coward | about 7 months ago | (#45758777)

It was modded down simply because the poster had the temerity to say something against the great god Canonical.

Personally, I gave up on *buntu around the 10/10 release and moved to two distros. CentOS for my servers and main laptop and Fedora for my play machine. Now I have stable systems. Yes, I could have got that with Debian. I started using Linux with Debian more than 10 years ago but got seduced by the Ubuntu spells. I went to a RH based distro simply because my employers are replacing their Windows 2003 servers with RHEL. No we don't use Sharepoint, IIS or any other MS crapware but software from the likes of Oracle and IBM.
I don't regret moving to CentOS. It is really stable and (currently) has the advantage of still using Gnome2. Yay!

Canonical has IMHO lost the plot.

Ubuntu: Linux for Amazons! (-1)

Anonymous Coward | about 7 months ago | (#45757207)

it puckered my sphincter when I heard of the spyware.

TRIM? who needs it! (3, Insightful)

sshir (623215) | about 7 months ago | (#45757231)

Well, if you don't do random writes, you don't need TRIM.

How to get away from random writes you ask? Simple! Just use BTRFS.

"But my database!" you say. Well, the answer is simple - time to move away from 50 year old technology and to a modern database engine, the kind that doesn't do random writes either (fractal tree based, for example).

Disclaimer: All of the above is not written for stodgy "enterprise level" types.

Re:TRIM? who needs it! (0, Troll)

Anonymous Coward | about 7 months ago | (#45757265)

Yea it's written for braindead dot com wannabes who think hip barely usable technology is the meaning of life, and wonder why their shit products are unreliable.

Re:TRIM? who needs it! (0)

Anonymous Coward | about 7 months ago | (#45758217)

Yea it's written for braindead dot com wannabes who think hip barely usable technology is the meaning of life, and wonder why their shit products are unreliable.

Yeah, because an ancient rotting codebase running a database engine from last decade has pushed Slashdot to the top Silicon Valley's "What's Hot" list...

Re:TRIM? who needs it! (0)

Anonymous Coward | about 7 months ago | (#45757283)

What happens when your free space gets used up?

Re:TRIM? who needs it! (2, Funny)

Anonymous Coward | about 7 months ago | (#45757651)

partition Czechoslovakia

Re:TRIM? who needs it! (1)

fisted (2295862) | about 7 months ago | (#45757867)

then you balance it it (never mind the occasional data loss, we have more than enough data anyway)!
i hear balance is the ultimate solution for any btrfs problem.

ran out of free space? balance it!
bad filesystem corruption after power loss? balance it!
faulty blocks? balance it!
tree not balanced? balance it!
neighbor's dog taking a dump on your lawn? get the hell off m^W^W^W^W^W balance it!

i think you kind of get the idea

Re:TRIM? who needs it! (0)

Anonymous Coward | about 7 months ago | (#45757309)

Let the parent post be a lesson to everyone: never go full retard.

Re:TRIM? who needs it! (1)

fnj (64210) | about 7 months ago | (#45758121)

How to get away from random writes you ask? Simple! Just use BTRFS.

Or you could use ZFS, which is an actual mature and reliable system which uses COW.

Re:TRIM? who needs it! (1)

sshir (623215) | about 7 months ago | (#45758157)

Sure, ZFS is alright too, but where's the excitement in that? :)

Re:TRIM? who needs it! (2)

TheDauthi (219285) | about 7 months ago | (#45758233)

Excitement is a bug - not a feature - in a filesystem.

Re:TRIM? who needs it! (2)

LordLimecat (1103839) | about 7 months ago | (#45758463)

Im not entirely sure you understand what TRIM does. Its not to get rid of random writes, its to deal with a scenario where you have written and deleted 120GB from a 120GB SSD. Your OS has marked 120GB as "deleted", but those blocks are still occupied and cannot be re-written until they are first erased. This incurs a penalty, particularly since the erase block size is typically larger than the FS cluster size.

Re:TRIM? who needs it! (1)

jones_supa (887896) | about 7 months ago | (#45758545)

That is not completely accurate either. The main purpose of TRIM is to inform the disk which areas are not used by the file system so that they can be safely overwritten by remapped data for wear leveling purposes.

Re:TRIM? who needs it! (2)

LordLimecat (1103839) | about 7 months ago | (#45758645)

That is not correct: its not about doing anything safely or even about wear-leveling. The filesystem is what handles writes, and it knows where is safe to write to, and wear-leveling is helped by TRIM but that is not what TRIM actually does.

TRIM simply informs the drive that it can perform an erase on a particular block when the filesystem marks it as deleted. This is so that any erases or remapping that needs to happen can e done when the drive is idle-- basically, it triggers garbage collection. With TRIM and auto-garbage collection off, the drive into a brick wall when it needs to write 10GB of data and it turns out that there are no already blanked blocks available; in that case it would have to do read-erase-writes for 10GB or more (due to amplification) worth of blocks, slowing everything to a relative crawl.

Just about everything an SSD does is improved by garbage collection, and TRIM is just OS- / FS- triggered garbage collection.

Re:TRIM? who needs it! (0)

Anonymous Coward | about 7 months ago | (#45758727)

That is not completely accurate either. The main purpose of TRIM is to inform the disk which areas are not used by the file system so that they can be safely overwritten by remapped data for wear leveling purposes.

Why do you call it the main purpose, you don't get wear leveling without also fixing the performance problem, but you can get write performance without doing wear leveling if you wanted, and do wear leveling in the filesystem or something.

Why would anyone even CARE if their SSD had horribly degraded write performance.. but you could use it longer that way by fucking with your OS to send additional IO commands... Whoopedeedooo...

NOT COOL! (-1)

Anonymous Coward | about 7 months ago | (#45757281)

1. It's 2013. Why are you still referring to womyn as trim?

2. Real women use gentoo.

Re: NOT COOL! (-1)

Anonymous Coward | about 7 months ago | (#45758141)

Die freak

wTF Windows 7 had this 4 years ago (1)

Billly Gates (198444) | about 7 months ago | (#45757293)

And supports vectors of ranges to Trim. Does it support this spec yet?

Come on.

Good News for Mint Enthusiasts (0)

ohnocitizen (1951674) | about 7 months ago | (#45757525)

Is it bad that my first thought when reading this was "cool, when will Mint get this"?

Re:Good News for Mint Enthusiasts (0)

Anonymous Coward | about 7 months ago | (#45757625)

and 5 years ago the sentiment was "cool, when will Ubuntu get this"?

Re:Good News for Mint Enthusiasts (0)

fisted (2295862) | about 7 months ago | (#45757881)

this is about a default setting, you ignorant fuck.

Re:Good News for Mint Enthusiasts (0)

ohnocitizen (1951674) | about 7 months ago | (#45758409)

Ah, the famously friendly linux community! Hahahaha seriously though, if someone doesn't know something and you do, it doesn't hurt to be friendly about it :)

Out-of-the-box? (4, Informative)

rossdee (243626) | about 7 months ago | (#45757737)

Does Linux come in a box these days, I thought you just downloaded it, and didn't have to pay for it and the packaging...

Re:Out-of-the-box? (0)

jones_supa (887896) | about 7 months ago | (#45757829)

If you paid for it, the full SSD support would have been in place at the same time the first drives rolled out to the market.

Re:Out-of-the-box? (1)

SeaFox (739806) | about 7 months ago | (#45758429)

I find the term "out-of-the-box" much preferable to "baked-in", which they are even using to describe built-in features on software nowadays.

Re:Out-of-the-box? (0)

Anonymous Coward | about 7 months ago | (#45758899)

Boxed version come with a zealot's handbook, 8x10 autographed picture of Linux Torvalds, and a bag of toejam hand picked from Richard Stallman's feet.

Re:Out-of-the-box? (1)

fph il quozientatore (971015) | about 7 months ago | (#45758973)

Sure, it will come in a box, as did the previous stable version [canonical.com] .

Linux Sucks (-1)

Anonymous Coward | about 7 months ago | (#45757937)

Ubuntu: 4 years behind Windows.

I recently Trimmed (0, Offtopic)

Dan Askme (2895283) | about 7 months ago | (#45758755)

Me and misses did the monthly LTS trim of our immediate bush gardens. Performance hasnt really improved, and, stability cums and goes. This is a known issues when running a bloated OS like Ubuntu on critical hardware systems.

We recently made a switch to a pure Debian based bush garden, the performance is superb. Too bad its over within a second or two.

Get in there! Pre Xmas drink banter!

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