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Facebook Experimenting With Blu-ray As a Storage Medium
s122604 links to CNN's explanation of what may be the future of cold (or at least lukewarm) storage at Facebook, which is experimenting with massive arrays of Blu-Ray discs for seldom-accessed user files. Says the report: The discs are held in groups of 12 in locked cartridges and are extracted by a robotic arm whenever they're needed.
One rack contains 10,000 discs, and is capable of storing a petabyte of data, or one million gigabytes.
Blu-ray discs offer a number of advantages versus hard drives. For one thing, the discs are more resilient: they're water- and dust-resistant, and better able to withstand temperature swings. Their data can be restored more quickly, and they're easier to transport.
Most important, though, is cost. Because the Blu-ray system doesn't need to be powered when the discs aren't in use, it uses 80% less power than the hard-drive arrangement, cutting overall costs in half.
... those drives offline or come up with a system to power up the drives via custom san hardware when you want to access them? With facebooks cash it should be do-able.
Can I ask Facebook to delete my stuff from one of those (assuming I had a Facebook account in the first place)
Enterprises have been doing this with tape for 30 years.
In fact, modern tape technology probably has a higher "volumetric" density than BD.
"I don't know, therefore Aliens" Wafflebox1
When you first access this data, you have to sit through 42 previews before you get to it.
It was a joke! When you give me that look it was a joke.
Couldn't get all the way to the 7th sentence of the summary?
I read TFA. They're not using them as "storage" in the sense of active, accessible storage. It's a backup system.
What they're trying is, instead of storing redundant copies of everything on multiple drives (for resilience and geolocality), they're keeping one copy live and keeping backups on blu-ray.
So there's never a latency of minutes while it loads data from Blu-Ray, you just might be routed to Siberia or something to get the one active copy. If that copy's bad, error (restore from backup during next nightly batch or something).
"Those data demands will only increase with time, particularly as personal cameras and smartphones become capable of capturing higher-quality images."
From Facebook: "We automatically take care of resizing and formatting your photos for you when you add them to Facebook."
It little behooves the best of us to comment on the rest of us.
That's not really how tape systems work. Generally they keep an index online so you can tell the tape system to pop in a specific tape and goto a specific position, longest load times... in real world that i've personally witnessed... 10 mins
I dunno. I've never been pleased with the performance of optical media. I'd think being in a data center, heating up and cooling down from usage and storage is going to have very bad effects on recordable optical discs (CDs, DVDs, Blurays). Not to mention, it's always a pretty well known fact, consumer recorded media (the ones with dyes and stuff) aren't terribly reliable in the long term. My personal experience with recordable optical media is poor at best, I have very very few discs that've remained readable and error free after just five years of relatively decent care and storage. And this is not even using them every day, heating them up and cooling them down, just stored in a dark cool place.
Seems... overhyped. I simply can't come to believe this is an actual viable storage medium for any kind of large scale operation. But enh, if it works for them, good deal. Seems like you'd get more bang for your buck using high capacity tapes which hold up much better to heating up and cooling down.
The power saving claim also seems silly. This could be easy done with standard hard drives in a cartridge type system they're saying they're using, powering down unused drives and putting them into a storage position (though for me, I think it'd be much smarter to make the connector the moving part and just plug into the right bank of HDs, instead of moving HDs around in a cartridge.)
The more I think about this operation, the less intelligent and efficient it seems to be.
Okay, so we need disc 101 from tray 1010101 and the robot arm is busy, three other fetches already in the queue. After 30,000ms client Javascript times out and substitutes a "retrieving data, re-try for a few minutes" place holder, sets a longer camp-on timeout and releases the request.
The reason the robotic arm is busy is that despite random assignment to storage pools with some localized album grouping, web crawler activity for public albums, and bulk pre-fetch requests for semi-private albums by browser plugins run by logged-in users (which became more popular as access time increased) ... the lukewarm storage facilities are running hot and queues are full most of the time.
Despite the polished and smoothly functioning presentation that encourages the users to "just wait a bit" ... a dark rumor grows deep in the hearts of many that the data is not merely delayed, they must brush off dust and cobwebs, or root for it because it had been haphazardly tossed into a pile of rubbish somewhere, relegated to the digital Basement. Facebook does not think your photograph is of sufficient merit. Grandmother has long passed and you had not wished to look at her last week, so... why should you be interested now?
The effects are complex, but the cause is clear: the Internet is perverse. It re-routes around any attempt to take immediate access data off-line by degrees, accomplishing this through a series of countermeasures such as unwelcome crawlers depleting your cache, hitting your 'public' cold data systematically and regularly, then finally bankrupting your company as users migrate to another service whose superior performance does not arise from superior engineering -- merely the fact that fewer users are using it.
So the moral of the story is, if you are Facebook and wish to remain so, you will either strive to find a way to keep the random access time for everything down below 2000ms -- or die.
And also, Facebook would be wise to heed the following:
once / forgotten by tourists / a bicycle joined a herd of mountain goats /// with its splendidly turned horns / it became / their leader /// with its bell / it warned them / of danger /// with them / it partook / in romps / on the snow covered / glade /// the bicycle / gazed from above / on people walking; / with the goats /// it fought / over a goat, / with a bearded buck /// it reared up at eagles / enraged / on its back wheel /// it was happy / though it never / nibbled at grass /// or drank from a stream /// until once / a poacher / shot it /// tempted / by the silver trophy / of its horns /// and then / above the Tatras was seen / against the sparkling / January sky /// the angel of death erect / slowly / riding to heaven / holding the bicycle's / dead horns //////~Jerzy Harasymowicz
<blink>down the rabbit hole</blink>