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Vibration Killing Enterprise Disk Performance?

timothy posted more than 4 years ago | from the aftershocks-even-worse dept.

Data Storage 159

An anonymous reader writes "Is vibration killing disk performance? ZDnet reports on research that a carbon fiber anti-vibration rack increased random read performance by 56% to 246% and random write [performance] by 34% to 88%. Vibration is a known disk problem, but this is one of the few attempts to quantify its impact — which looks to be much greater than suspected."

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Interesting. (-1, Redundant)

Anonymous Coward | more than 4 years ago | (#32133930)

Geeks shouldn't have a vibration problem because their bed is only used for sleeping.

Females... (-1, Troll)

Anonymous Coward | more than 4 years ago | (#32133954)

females report a 245% increase in performance with vibrating dicks.

Re:Females... (1)

Daengbo (523424) | more than 4 years ago | (#32135122)

My dick is enterprising, and vibrations always increase its performance. Oh, dicks. Sorry. Forget I said anything.

Re:Females... (1)

Daengbo (523424) | more than 4 years ago | (#32135134)

Yeahhhh. Disks, not dicks. I even previewed.

Re:Females... (2, Funny)

setagllib (753300) | more than 4 years ago | (#32135728)

Paging Dr. Freud...

Hmmm... (2, Funny)

antifoidulus (807088) | more than 4 years ago | (#32133958)

So maybe sex in the server room IS a good idea! Not to mention all the puns you can make about racks.

Re:Hmmm... (5, Funny)

Anonymous Coward | more than 4 years ago | (#32134042)

Get off my Rack?

In Soviet Russia, rack vibrates you?

All your rack.....?

Re:Hmmm... (-1, Redundant)

raving griff (1157645) | more than 4 years ago | (#32134378)

Not to mention all the puns you can make about racks.

Get off my Rack?

In Soviet Russia, rack vibrates you?

All your rack.....?

A perfect example of why this type of joke flies right over the average /.er's head.

Re:Hmmm... (3, Informative)

thePowerOfGrayskull (905905) | more than 4 years ago | (#32135230)

A perfect example of why this type of joke flies right over the average /.er's head.

So perfect, indeed...

Re:Hmmm... (1)

mysidia (191772) | more than 4 years ago | (#32136328)

I'm racking my brain, trying to figure out what all this vibration stuff is about.

Re:Hmmm... (1, Funny)

Anonymous Coward | more than 4 years ago | (#32135544)

In Soviet Japan, 512mb is a rack of lamb

Re:Hmmm... (0)

winkydink (650484) | more than 4 years ago | (#32134068)

And to think, people wonder why geeks don't get laid more.

Re:Hmmm... (0, Flamebait)

Anonymous Coward | more than 4 years ago | (#32134350)

Probably fear of sexual harassment charges for making harmless jokes that most women can and do enjoy.

The woman you'd offend with "rack" and "hard disk" jokes is the woman who wouldn't do you anyway because she's a militant mulleted bull-dyke, with a degree in womens' studies, who bench-presses two-fifty and tapes her enlarged clitoris between her legs.

Re:Hmmm... (1)

Hurricane78 (562437) | more than 4 years ago | (#32134408)

Yeah, because those people in school that got lots of girls didn’t constantly make jokes about sex, while the geeks constantly talked about geeky stuff...

It’s not whether you make the jokes, but how you act while doing so. Confident, or ashamed?
Most geeks seem to be ashamed of her noticing that they would want sex with her.
While the playboys see it as a compliment, making her special, because amongst a thousand girls, he chose her.

And what most geeks don’t seem to know: The can see that. The microexpressions, the little changes in intonation, the posture, everything in you tells her how you meant it. And women don’t care much what you say. They care how you say it, and especially how that feels.

Re:Hmmm... (1)

zach_the_lizard (1317619) | more than 4 years ago | (#32135214)

Yep, that's totally true. Confidence is one of the keys to attracting women. As someone who suffered from depression and then recovered, I can tell you the change in female interest has been extremely noticeable. I haven't gained or lost any weight, changed my looks, or done anything superficial, but the interest has certainly heightened. I do joke about how we nerds never get laid, but, yes, we do get laid, and we do get women.

Re:Hmmm... (0)

Anonymous Coward | more than 4 years ago | (#32136132)

If only confidence fixed ugly.

Re:Hmmm... (1)

http (589131) | more than 4 years ago | (#32136828)

Oh, and don't forget that not one girl was ever self-conscious, ashamed, or interested in something other than sex. Your attempt at sociology fails. Hint: sexist generalizations contributed to your post's downfall.
Males have no monopoly on botching the interpretation of social cues.

Re:Hmmm... (1)

Alistair O'Twill (1791170) | more than 4 years ago | (#32135010)

I was about to leave a snarky comment but after reading the other comments I had to concede to winkydink's opinion.

shouting at disks (4, Interesting)

Anonymous Coward | more than 4 years ago | (#32134778)

So maybe sex in the server room IS a good idea! Not to mention all the puns you can make about racks.

Also, don't shout at your disks since it increases latency, as the guys at Sun Storage learned:

http://www.youtube.com/watch?v=tDacjrSCeq4

Re:Hmmm... (0)

Anonymous Coward | more than 4 years ago | (#32134916)

And imagine how much worse it would be if it was more than just you in there!

Old news is old (5, Informative)

Anonymous Coward | more than 4 years ago | (#32133976)

Yes, already saw some crazed guy at Sun shout into an array of HDDs and it decreased performance.

http://www.youtube.com/watch?v=tDacjrSCeq4

Re:Old news is old (0)

Anonymous Coward | more than 4 years ago | (#32134566)

I loved when he shouted in to it.
And the impact was also pretty damn high as well, that was what i never expected at all.

JBODs... i feel dirty.
I bet i can make some people puke. A RAID of JBODs

Re:Old news is old (0)

lawpoop (604919) | more than 4 years ago | (#32135506)

Upvoted for reddit meme infecting slashdot headline. Sneaky cat is sneaky.

Re:Old news is old (1)

adisakp (705706) | more than 4 years ago | (#32135570)

That datacenter is loud as hell. I wonder how much faster their disks would perform if they could get the datacenter quieter.

Play Stravinsky to your HDs (0)

Anonymous Coward | more than 4 years ago | (#32136138)

What about playing Stravinsky? Are HDs really plants in disguise?

That Aussi built a bad data center.... (0)

Anonymous Coward | more than 4 years ago | (#32136184)

That idiot has the loudest data center I have ever heard.

I drive a big rig ( International Pro Star Eagle ) and its a *LOT* quieter than his data center.

The data centers I have been in both have large fans ( low noise, high volume ), and sound dampining on the walls.
The individual racks were bolted to concrete. Duh!

Didnt Compaq and HP used to have rubber mounting brackets?

( Funny! My Capata is 'Idiocy'

Re:That Aussi built a bad data center.... (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#32136348)

It's spelt Aussie.

That's (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#32134038)

What she said.

Sun engineers catching disk vibration in the act (0, Redundant)

Anonymous Coward | more than 4 years ago | (#32134086)

If you want to have a laugh, check out Bryan Cantrill (Mr. DTrace) and Sun engineer Brendan Gregg shouting at disks and checking out latency heat graphs on YouTube:

http://www.youtube.com/watch?v=tDacjrSCeq4

Interesting! (0)

Anonymous Coward | more than 4 years ago | (#32134094)

I wonder how much this could affect the capacity of harddrives

Re:Interesting! (1)

X0563511 (793323) | more than 4 years ago | (#32134206)

This has nothing to do with capacity, you idiot! At least read the summary would you?

Star Trek (4, Funny)

robvangelder (472838) | more than 4 years ago | (#32134100)

Did anyone else think "how is Kirk going get out of this one"?

Re:Star Trek (1)

lemur3 (997863) | more than 4 years ago | (#32134222)

Did anyone else think "how is Kirk going get out of this one"?

do not feel bad, I too thought the same thing....

damn you kirk!!

Re:Star Trek (3, Funny)

Bugamn (1769722) | more than 4 years ago | (#32134470)

Using inertial dampers [memory-alpha.org] ?

Re:Star Trek (1)

Tablizer (95088) | more than 4 years ago | (#32135502)

Kh-a-a-a-a-a-a-an! Stop shaking Me-e-e-e-e!

not surprising really (5, Interesting)

v1 (525388) | more than 4 years ago | (#32134110)

It's a lot easier to interfere with a moving head arm than it is to mess one up that's locked on a track, so this isn't surprising in the least for vibration to affect reads that require numerous long seeks. I'm surprised it's not worse than they've found.

Moving the head requires accelerated head stepping to top speed, stepping to close to the track, slowing down, stopping at the destination track, waiting for the head to settle, and reading an address block to find out where you managed to land. If you find you missed the track, you have to go through the whole seek process again. (usually only once more, those short adjustment hops are pretty reliable because they're lower speed) But that really hurts your single block read time.

Add to that the fact that the "high performance" drives are making more risky higher speed track changes, which increase the odds of missing your target and make the operation more sensitive to vibration. I've written direct HDD io code before, and sure, you can up the step speed to get very nice seek time boosts, but then you start missing your track and start getting reseeks. Usually you go with the fastest that's acceptably reliable, and that puts you on the bleeding edge of having problems, where things like vibration can run you off the deep end of the bell curve.

It wouldn't surprise me one bit if 50% of the "high performance drive" better speed is due to faster spindle speed, and the other half is faster (riskier) seek speed.

Re:not surprising really (2, Insightful)

pspahn (1175617) | more than 4 years ago | (#32134208)

How difficult would it be to account for this vibration performance degradation in such a case?

If you had some kind of vibration sensor that measured vibration levels, couldn't it then talk back to code telling it to slow down because there's too much vibration?

Re:not surprising really (2, Informative)

v1 (525388) | more than 4 years ago | (#32135006)

should be possible to add a sensor (probably even on silicon) that can warn of higher vibration and slow the stepping, but I bet they don't do that right now.

Re:not surprising really (1)

pla (258480) | more than 4 years ago | (#32135592)

If you had some kind of vibration sensor that measured vibration levels, couldn't it then talk back to code telling it to slow down because there's too much vibration?

I think you either overestimate the frequency of typical vibrations, or underestimate the speed at which your heads can theoretically seek.

A 15k drive can push around 180 IOPS. A typical human scream comes out at around 300Hz. 1.6 cycles really doesn't give enough of a sample to reliably detect (much less correct for) even they most predictable of sources of interference.

The situation gets somewhat better for lower-speed drives, but consider that most real-world vibrations won't come from humans, but rather will involve some harmonic of 60HZ (or 50Hz, depending on your local AC frequency). Even a 7200RPM drive can push 90IOPS, making a 120Hz source of interference come out to a mere 1.33 cycles.

So long story short - Yeah, you can detect (and correct for) fairly repetitive sources of vibration. The most common real-world sources of such vibrations, however, occur at a low enough frequency that you won't see enough of the interference per seek to meaningfully do anything about it.

Re:not surprising really (1)

omglolbah (731566) | more than 4 years ago | (#32135754)

Wouldnt it be possible to start out running balls to the wall on spin-up and do a gradual back-off if you encounter reseeks due to missing tracks?
An algorithm for this would of course need to be created but to me this seems like the sensible way to get dynamic handling of noise.

Re:not surprising really (1)

TheKidWho (705796) | more than 4 years ago | (#32134252)

What they need to do is hire some mechanical engineers that deal with vibrations. There are many many ways to deal with vibrations.

Re:not surprising really (4, Interesting)

PopeRatzo (965947) | more than 4 years ago | (#32134600)

For the computers in my music project studio, I've always used Scythe stabilizers for my hard drives, mostly to keep the sound down.

But now that I think about it, the drives in my raid box are like 4 years old and not one has failed. I've thought about buying new drives to replace them, but as long as they're working and everything is backed up, I haven't bothered.

I don't know if the stabilizers have had any effect on their longevity, but the little bit of care I take with vibration dampening when I build machines sure has resulted in some quiet machines.

Re:not surprising really (1)

X0563511 (793323) | more than 4 years ago | (#32135434)

I found a 6 year old Western Digital IDE drive in our DC.

This thing has lived through loud noise, vibration, bad power, failed AC (and so high temps) but kept on truckin'

I think you get a proper specimen once in a great while heh.

Re:not surprising really (1)

noidentity (188756) | more than 4 years ago | (#32134632)

Moving the head requires accelerated head stepping to top speed, stepping to close to the track

I just want to point out that hard drives stopped using stepper motors [wikipedia.org] decades ago. They've used voice coils [wikipedia.org] since, which is basically an electromagnet and strong magnet which it deflects to various positions based on the field strength; in other words, it's continuous, not discrete like a stepper motor (though they can do microstepping [wikipedia.org] as well). OK, so in a way, a voice coil is sort of like a stepper motor with only one phase, which is then microstepped...

Re:not surprising really (3, Informative)

Laser Dan (707106) | more than 4 years ago | (#32135024)

Moving the head requires accelerated head stepping to top speed, stepping to close to the track

I just want to point out that hard drives stopped using stepper motors [wikipedia.org] decades ago. They've used voice coils [wikipedia.org] since, which is basically an electromagnet and strong magnet which it deflects to various positions based on the field strength; in other words, it's continuous, not discrete like a stepper motor (though they can do microstepping [wikipedia.org] as well). OK, so in a way, a voice coil is sort of like a stepper motor with only one phase, which is then microstepped...

Well you are half right, but so is the GP.
The GP's description is more accurate if you replace "stepping" with "accelerating".

The head does not move to a position based on field strength (open loop control). It is free to move on low friction bearings, the applied field strength accelerates the head. Closed loop control is needed to make it stop at the correct position.

Re:not surprising really (1)

aaarrrgggh (9205) | more than 4 years ago | (#32134772)

The only thing surprising is that manufacturer data didn't support this big of an impact. We tried to stay three orders of magnitude below acceptable vibration limits and assumed that was adequate. While I haven't tied an accelerometer to a rack or drive chassis, it sounds like they aren't managing internal vibration as well as they need to.

Re:not surprising really (1)

afidel (530433) | more than 4 years ago | (#32135726)

Actually the disk manufacturers have this information (at least Seagate does) through their former SAN division that they sold to Xiotech. One of the big improvements in performance that they were able to get in their sealed disk packs (ISE) was through vibration reduction by placing the drives on a rigid frame and mounting them in such a way that the vibration from multiple spindles canceled. The other big performance improver was stripping two decades of compatibility code out of the firmware and talking more directly to the platters.

Re:not surprising really (1)

suomynonAyletamitlU (1618513) | more than 4 years ago | (#32135088)

Well, okay, that's an intriguing data point. Where is the seek speed set, though? In the OS, BIOS, some kind of per-drive firmware, or is it set by the hardware itself?

It seems like if vibration is causing re-seeking in general, you could cut the seek speed for all the drives in a data center to limit the problem. I'm kind of surprised that something as precision-oriented as (what are now) super-capacity hard drives don't have any accounting for this, when if that's the solution, they should have been right up there with fan controls as a reasonable tweak for overclockers.

Or if they do, I'm pretty sure I've never heard about it.

Need more SSD? (0)

Anonymous Coward | more than 4 years ago | (#32134138)

I'm guessing SSDs will help here.

Re:Need more SSD? (1)

Skapare (16644) | more than 4 years ago | (#32134338)

They can, but they may not be the least cost way.

Anyone know why it affects SSD? (1)

Rivalz (1431453) | more than 4 years ago | (#32134148)

I'm just curious why SSD is also prone to the problem.

Re:Anyone know why it affects SSD? (4, Informative)

MarcoAtWork (28889) | more than 4 years ago | (#32134182)

the article does not say that it affects SSDs, but that it affects the SSD value proposition (aka, if you can spend little $$$ on carbon rack enclosures and get a significant seek performance increase, spending the large amount of $$$ to go full-ssd might not be as cost effective).

Re:Anyone know why it affects SSD? (1)

Svartalf (2997) | more than 4 years ago | (#32134842)

It depends on the application as to whether you're going to improve the value proposition. Some applications will cost nearly as much as the SSDs when you apply the vibration compensation stuff to the system. Once you get there, the temperature, power, and overall lifespan issues still are present- and you're not getting rid of those any easier than you did with just the vibration problem alone.

Re:Anyone know why it affects SSD? (3, Insightful)

bertok (226922) | more than 4 years ago | (#32135190)

the article does not say that it affects SSDs, but that it affects the SSD value proposition (aka, if you can spend little $$$ on carbon rack enclosures and get a significant seek performance increase, spending the large amount of $$$ to go full-ssd might not be as cost effective).

My over one year old SSD drive can do ~6,000 under a database workload, the next-gen consumer SSD drives are reaching 60,000 random IOPS, and there are enterprise drives that can do over 150,000 IOPS with streaming speeds over a gigabyte per second.

This is a little like saying that Hayes has released a new 56K modem that resists line noise 50% better than existing modems, which affects the value proposition of 1Gbps fibre.

There's also no need to go "Full SSD". The newer virtualizing SAN arrays can migrate individual blocks of data between tiers of storage to place everything on the appropriate storage depending on the need for performance.

Re:Anyone know why it affects SSD? (1)

X0563511 (793323) | more than 4 years ago | (#32134220)

It shouldn't, and a quick skim didn't reveal that either.

Are you sure you didn't just misread an acronym?

Re:Anyone know why it affects SSD? (1)

aXi (6533) | more than 4 years ago | (#32134238)

exactly my thoughts, I know for a fact I have never had lower read or write cycles while running around with my laptop with a CF-Drive.

Re:Anyone know why it affects SSD? (3, Insightful)

InsertWittyNameHere (1438813) | more than 4 years ago | (#32134264)

I don't think it is. I always see "no vibration/movement issues" listed as a "pro" in all SSD vs HDD reviews. Plus SSDs don't have any moving parts.

Is you comment based on this part of the article?

SSD value. Flash SSDs have fast random read access. But disks can improve their performance by 50% through vibration damping, that changes value proposition for SSDs.

I think the author is saying that if you can improve performance by 50% then there's less value in moving to SSDs that previously thought.

Re:Anyone know why it affects SSD? (1)

adolf (21054) | more than 4 years ago | (#32135380)

I think he's just being deliberately vague. It's an article about HDD performance as it relates to vibration, not an in-depth comparison between them and SSD.

Taken literally, the only thing he says is that the value proposition for SSD changes. But this change could be an improvement for an application's specific needs, or a detriment -- the author does not say.

The implied message (if there even is one) is that, perhaps, one should add "mechanical vibration" to their list of things to consider when selecting between hard disks and SSD.

I saw the presentation... (4, Informative)

georgewilliamherbert (211790) | more than 4 years ago | (#32134152)

..at SustainIT 2010, Turner had a really good analysis. Still some gaps - figuring out what frequencies hurt the most, and how individual drive types respond to what, is necessary followon. How various vendors' drive units transfer vibration from the rack into the unit, into the drive carrier, into the drive. That sort of thing. Now that the phenomena is identified, a lot more to do on it.

At the least, keep performance sensitive drives away from large sources of environmental vibration, such as your AC unit and so forth.

Re:I saw the presentation... (0)

Anonymous Coward | more than 4 years ago | (#32134664)

Or keep them away from your case and cpu fans....

Carbon Fibre (1, Funny)

Anonymous Coward | more than 4 years ago | (#32134194)

...a carbon fiber anti-vibration rack...

What is this? Pimp My Rack?; "Next up we'll add a tinted front door, lower the rack by an inch and fit it with diamond-encrusted rack nuts."

Can't believe it (3, Insightful)

lalena (1221394) | more than 4 years ago | (#32134232)

From the article:

that CS disk drives are more sensitive to the vibration from physically coupled adjacent disk drives.

and

The problem is that most civilians don’t understand the problem and are not willing to pay to solve it.

Why should most people care about vibration caused by adjacent drives if most people only have one drive.

The other issue from TFA is that I can't believe a different rack can cause 250% performance improvement, unless you really stacked the deck against steel racks - loose screws, hard drives not properly mounted...? I assume this means that current server racks see I/O rates that are only 40% of what is advertised by manufacturers. Are we expected to believe that no one has noticed this? What about multiple drives in a server. There is no rack separating those drives. This reads like marketing, not real research.
http://www.greenplatformcorp.com/ [greenplatformcorp.com] is the site if you are interested and the "research" is several months old.

Re:Can't believe it (5, Interesting)

georgewilliamherbert (211790) | more than 4 years ago | (#32134298)

I've done some quick and dirty followups. Drive arrays on a concrete floor are much faster than those in a normal steel or aluminum rack with more drive arrays.

This is real.

You can demonstrate it with one drive array, a rack, and a solid floor. Put other equipment in the rack. Put the array in, test it. Stop testing, put it on the floor, start testing again. Put it back in the rack, test it again. The floor, test it again.

There are some time delays involved as the drives adapt to higher and lower vibration environment - the mechanism here is the drive seems to be adopting a strategy of more error correction on reads and writes when it thinks the head's vibrating more. It will ramp that up and down as it figures out that the environment has changed.

Re:Can't believe it (1)

aaarrrgggh (9205) | more than 4 years ago | (#32134814)

Repeat your experiment using rubber washers to isolate chassis from rack. The rack can act as a tuning fork...

Re:Can't believe it (0)

Anonymous Coward | more than 4 years ago | (#32134306)

Why should most people care about vibration caused by adjacent drives if most people only have one drive.

I hope to $DEITY that you do not admin ANY server on $DEITY'S green earth!

Re:Can't believe it (2, Informative)

Burning1 (204959) | more than 4 years ago | (#32134366)

Why should most people care about vibration caused by adjacent drives if most people only have one drive.

Some of the largest consumers of hard disks are enterprise companies with network attached storage, storage area networks, and RAID equipped servers.

These companies have a very high density of hard disks, and spend a lot of money for high performance. It's not unheard of for such a company to purchase a huge array, not for capacity purposes, but for seek time and throughput.

I'm sure they care.

Re:Can't believe it (1)

MikeBabcock (65886) | more than 4 years ago | (#32134926)

At least some enterprise SCSI hard drives share data between each other so as to predict when each others' head movements will affect other drives. When four (for example) drives are mounted vertically under each other in a cage of any form, the sudden movement of the drive head for one drive induces some momentum in the nearby drives. Attempting to compensate for this leads to better performance whether people are aware of it happening or not, and thus higher sales.

Whenever possible I test drives (along with other components) mounted in the system they will be used in to assess accurate situational performance. Drive performance solo on a table is not nearly as useful if you do in fact have more than one drive in use.

At home I use Antec cases with vibration isolation mounts, FYI.

Re:Can't believe it (4, Interesting)

KahabutDieDrake (1515139) | more than 4 years ago | (#32135138)

Walk over to the nearest properly mounted rack array you have, and shake it. Does it move visibly? If so, problem identified. Most racks are built to hold things up. They aren't built with much structural integrity beyond what is absolutely needed. I've seldom seen a rack with any kind of proper cross bracing, and this makes them prone to vibration transfer. You make a valid point that this is presented as a "buy this product to improve your servers" kinda thing. However, the issues with vibrations have long been ignored, and maybe that needs to change.

My personal anecdote is: Working for a small company dealing in terabytes of data (7 years ago), they got their first disk array. Previous to that, they were using desktops to store everything around the network. So, after months of pleading, they got me the disk array I wanted, and the failure rate was atrocious. Averaged to 1 disk per 90 days. The SAN we used sat on a flimsy filing cabinet right next to a high speed printer. Not touching, but close. After a while of trying to figure out the problem, I finally sold the bosses on the idea of turning one of the closets into a server room. I installed a rack, mounted it to the wall with dampeners, and installed the SAN into it. Along with 2 1au servers, and another brand new NAS. The failure rate plummeted. The original SAN so prone to killing disks worked it's ass off for 2 more years before any of the drives failed again. As far as I know it's only had 3 disks replaced in the 5 years since then. Seems reasonable to me to assume that vibration not only plays a role in performance, but in lifetime as well.

Re:Can't believe it (1)

X0563511 (793323) | more than 4 years ago | (#32135494)

I would advise against shaking random racks in your datacenter. That can make Bad Things (TM) happen :)

Re:Can't believe it (1)

afidel (530433) | more than 4 years ago | (#32135798)

Buy better racks then, APC makes racks that are quite rigid with the side panels on as do other manufacturers.

Re:Can't believe it (3, Informative)

Angst Badger (8636) | more than 4 years ago | (#32135580)

unless you really stacked the deck against steel racks - loose screws, hard drives not properly mounted...?

Depending on where exactly they are, loose screws might actually help you. Tight metal-to-metal connections are much better at transferring vibrations, especially the higher frequency ones, than looser connections, where some of the vibrational energy is converted into lower-frequency vibrations. Steel is insanely good at carrying vibrations over long distances, hence the old movie trick of listening to railroad tracks for a train in the distance, or tapping on pipes in Morse code to communicate your escape plans to the inmate several cells over. (At the risk of veering off-topic, neither of these tricks work nearly as well in real life as in the movies, but they do work. Well, at least the railroad tracks do. Since the MPAA hasn't found my gargantuan mp3 collection yet, I haven't had a chance to test prison telegraphy yet.)

One thing that has always baffled me is why racks and computer cases are made of metal to begin with. There are, of course, certain areas where you need steel or aluminum for strength or carrying waste heat, but wood or plastic would do a much better job of damping vibrations. There's a reason audio speaker cabinets are made out of crappy, soft stuff like particle board: you don't want the cabinet to resonate, and particle board does a wonderfully poor job of transmitting vibrations, which is why it isn't used in guitars, where you want strong resonance. There are also a wide variety of synthetic rubbers like neoprene and sorbothane that do a good job of absorbing vibrations. Neoprene is cheap, and sorbothane, while more expensive, is still affordable and does such a good job of deadening vibration that it feels remarkably like meat. (I happen to have a square foot of it sitting on the counter next to me, waiting to be used in some vibration-damping experiments with my scooter, but having RTFA, I think I'll try using a little bit to replace the rubber pads on the bottom of my external drive enclosures.)

good vibrations? (2, Funny)

ncohafmuta (577957) | more than 4 years ago | (#32134266)

i guess the beach boys were wrong about those vibrations.

damn (1)

resfilter (960880) | more than 4 years ago | (#32134278)

i have gone to great lengths to isolate my drives from the chassis of my systems to improve noise level (using rubber isolation mounts, shock cords, whatever)

the fact that the drive itself would not have as much mass holding it stationary never really entered into my decision making process... i just checked, and they do produce a substantial amount of vibration during seeks

perhaps i should have done some benchmarks

Few attempts? (1)

gatkinso (15975) | more than 4 years ago | (#32134280)

Seriously? Anyone who has developed airborne systems using COTS hardware has encountered this issue with spinning media.

Re:Few attempts? (1)

symbolset (646467) | more than 4 years ago | (#32135366)

This is only one of the problem with airborn systems. There's also the fact that racks in a datacenter don't move on three axes during normal operation - which is important when your data storage platform is the surface of a bunch of gyroscopes.

Re:Few attempts? (1)

Alastor187 (593341) | more than 4 years ago | (#32136146)

Seriously? Anyone who has developed airborne systems using COTS hardware has encountered this issue with spinning media.

It is not just airborne applications...ground vehicles are just as challenging, and I am sure ship-board electronics are also a challenge. I know of ground vehicle applications where the entire unit had to be mounted on isolators just to support the use of rotating media. Without isolators the qualification vibration levels would 1) prevent the harddrives from probably running the software, and 2) would cause the drives to fail mechanically (after only hours of testing).

As far as isolators go they are no free lunch. They can damp high energy or high frequency vibration but the trade off is very large displacements at low frequencies. So ultimately the space the unit requires is larger and that is never desirable.

This is what you get... (4, Interesting)

camperdave (969942) | more than 4 years ago | (#32134310)

This is what you get when you drag a magnetic head across a surface. The sooner we get rid of mechanical storage the better. Solids are more robust, more energy efficient, quicker, denser, lighter. Cost and longevity issues are coming along. Yes, lets ditch the antiques already!

Re:This is what you get... (0)

Anonymous Coward | more than 4 years ago | (#32134506)

Just as soon as the price is right, we all will!
Many of us already have.

Re:This is what you get... (0)

Anonymous Coward | more than 4 years ago | (#32134888)

- Cheap
- Fast
- High Capacity

Pick two

Re:This is what you get... (1)

Tridus (79566) | more than 4 years ago | (#32134922)

Denser? I don't see a lot of 2TB SSDs on the market.

Re:This is what you get... (1)

hitmark (640295) | more than 4 years ago | (#32135238)

i think you will find them being pcie cards, not 3.5" sata drives, as the drive shape limits chip numbers.

Re:This is what you get... (1)

atamido (1020905) | more than 4 years ago | (#32136644)

i think you will find them being pcie cards, not 3.5" sata drives, as the drive shape limits chip numbers.

All of the SSD drives that I've seen are 2.5" drives. I've often wondered why no one uses some simple heat sinks and packs the chips as dense as can be into a 3.5" form factor.

Re:This is what you get... (0)

Anonymous Coward | more than 4 years ago | (#32136540)

This is what you get when you drag a magnetic head across a surface. The sooner we get rid of mechanical storage the better. Solids are more robust, more energy efficient, quicker, denser, lighter. Cost and longevity issues are coming along. Yes, lets ditch the antiques already!

Problem is, SSD aren't useful in an enterprise situation since they degrade over time with usage [enterprise...eforum.com] and this isn't the issue with disk based HDs. If they can fix this then your more likely to see big businesses want them, but till then thats means possible loss of data and the need to upgrade hardware sooner.

Re:This is what you get... (1)

Angst Badger (8636) | more than 4 years ago | (#32136696)

The sooner we get rid of mechanical storage the better. Solids are more robust, more energy efficient, quicker, denser, lighter. Cost and longevity issues are coming along. Yes, lets ditch the antiques already!

We have quite a way to go before that's practical for high-capacity write-intensive applications. And, as always, we won't know how much longevity to expect until we get there: the manufacturers will make wildly optimistic guesses early on, switching to bald-faced lies later, the same as they've done with every other storage medium. If you want to ditch your antiques, I'll be happy to put them to use biding my time while the bleeding edge bleeds. ;)

Wow, that could explain this... (1)

ZorinLynx (31751) | more than 4 years ago | (#32134354)

I previously had a hard drive in my Mac Pro that was vibrating like crazy; it was making the entire machine vibrate, and all for only 80GB. It wasn't the boot drive, but rather a drive where I just had some random crap.

I decided getting rid of the vibration (and resulting buzzing sound) was more important than having a paltry 80GB more, so I copied the data off and yanked the drive. My machine seemed to boot and run quite a bit faster after wards. I was pleasantly surprised. My previous theory was that the drive was somehow causing a problem on the SATA bus that was slowing down the other drive. After reading this article now I realize the vibration was probably the reason.

That 80GB drive is now serving as a door stop (literally). :)

magnetic field (1)

ncohafmuta (577957) | more than 4 years ago | (#32134360)

i'd actually be interested in seeing if performance decreases in a drive due to the magnetic field of a adjacent drive.

Re:magnetic field (1)

DDLKermit007 (911046) | more than 4 years ago | (#32136226)

If you drop a SAS 15,000RPM & SATA 7,200RPM drive one on top of the other you'll see some wacky issues. Space em out and it gets WAY better.

Disks need alignment and balancing (2, Insightful)

NicknamesAreStupid (1040118) | more than 4 years ago | (#32134782)

Plus a lube job and, definitely, Window cleaning.

Just in time, too (3, Insightful)

Weaselmancer (533834) | more than 4 years ago | (#32134850)

This is news we needed 20 years ago. SSD is going to replace mechanical HD over the next couple of years making the whole vibration issue irrelevant.

Ah well better late than never I guess.

As expected (1)

antirelic (1030688) | more than 4 years ago | (#32134958)

I've always suspected this, but never really cared to address the issue in any meaningful way because wtf can you do about it? I've always hated metal racks, and all the "affordable" stabilization kits do not do much to transfer the vibration from fans and other moving parts from the servers. In fact, the metal racks make for a nice little conduit to help spread out vibration from server to server. The more full the rack, the more the impact.

Over the course of years, I've had plenty of pci cards shake lose for no apparent reason. People always wonder why parts fail, or come loose over time. I explain "vibration"... and then generally look at me like I have 2 heads. Just because you cant see it moving, doesnt mean it is not. And as far as servers grinding away 24/7, the vibration effect is cumulative, and measurable.

Now I have all the research that I need to run into work on Monday and demand we upgrade to a SSD SAN.... if only costs didnt matter.

This could be just a matter of resonance (3, Interesting)

melted (227442) | more than 4 years ago | (#32135026)

The disks all spin at roughly the same frequency (250Hz for a 15K RPM drive), so you could get some interesting resonance patterns in that frequency band as well as in its harmonics and frequencies that you get when you subtract rotational vibration spectrum of one drive from another. You can even hear these effects if you run two 7200 RPM drives in your desktop in a quiet room (assuming you don't have a dozen fans in the case that some people like to have for some reason).

The solutions is simple - dampen the drives to eliminate high frequency vibration transfer. Better yet, don't use screws to attach your drives at all. Use velcro.

Re:This could be just a matter of resonance (1)

evanbd (210358) | more than 4 years ago | (#32136296)

250Hz isn't high frequency; it's fairly low, as audio frequencies go. It's normally considered in the bass or low mid region. Wavelength will be > 1m in air, several times that in the materials making up the enclosure. Damping it out effectively and efficiently is not entirely trivial, though the obvious techniques like rubber mounts and the velcro you suggest will help a lot.

SSD (3, Interesting)

Ruvim (889012) | more than 4 years ago | (#32135044)

It is going to matter only until price for SolidStateDisks becomes in line with what it should be [businesswire.com]

SPONGE (-1, Troll)

Anonymous Coward | more than 4 years ago | (#32135280)

don't ffel 7hat [goat.cx]

Damn it Mr. Scott! (0, Redundant)

NevarMore (248971) | more than 4 years ago | (#32135644)

I cannae stop the vibrations cap'n. The flux cores are fissioning at 150% beyond their rated nebular rate!

Better have Geordi take a look... (1)

dousette (562546) | more than 4 years ago | (#32135976)

...because the intertial dampeners should really be smoothing these vibrations out!

Even screaming at disks works! (0)

Anonymous Coward | more than 4 years ago | (#32136248)

Indeed it's not new that we know vibrations can impact disk performances - even a few years back Slashdot pointed out an article on Sun performance probes, and how even screaming at an array of disks under load could visibly impact their performance!

Xiotech ISE (1)

cbdougla (769586) | more than 4 years ago | (#32136546)

I believe vibration is one of the things that Xiotech has tried address with their ISE bricks.

http://www.xiotech.com/ise-technology.php [xiotech.com]

I don't work for Xiotech. I just think it's a cool idea.

Carbon fibre here is silicon snake oil (1)

dbIII (701233) | more than 4 years ago | (#32136740)

About the last thing you would want is a light carbon fibre reinforced plastic rack if you want to damp vibrations. A well constrained steel rack with rubber washers would do a far better job because it is far stiffer for a start and you don't want to get much motion.
The answer is to learn from others. With high speed machine tools the trick for damping and stiffness is to use a very heavy base made from materials which damp the vibrations - such as grey cast iron where the damping effect from the graphite is from the portions that are at 90 degrees to what you get with fibre. The idea is to lose the energy of vibration between the poorly bonded graphite sheets and not to transmit it as you would get with a fibre.
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