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Where's my petabyte disk drive?

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Re: Where's my petabyte disk drive?

#41

He is wrong about 6TB being the biggest hard drive in the market. Now that SSDs have become the standard they are taking up the curve. Samsung announced a 16TB SSD last year. I don't expect people to devote as much effort to making spinning disks bigger. http://arstechnica.com/gadgets/2015/08/samsung-unveils-2-5-i...

The author also doesn't mention 'special' hard drives like Dropbox uses - 14 TB.

Re: Where's my petabyte disk drive?

#43
post #39
post #21

Earlier quoted context omitted.

It's a mystery to me that hybrid SSD+HD drives aren't more ubiquitous. I can guess what data is going to be read off the drive more frequently, but the computer can collect statistics and make a way more accurate prediction than I can.

I don't think statistics will make better predictions than I can. For example, consider a moderately large file (eg. 100MB), which is only ever read occasionally, by sequential low speed streaming. It seems reasonable to place it on the HD, but it's music, and I want it on the SSD so I can have the HD powered down for lower background noise when I'm listening to it. And I could have another almost identical file whic…

I'd assert that it could make a better prediction for the majority of the files stored on your drive. For example, even if it was technically feasable to do with separate drives, do you know which files in the global assembly cache should go on SSD versus HD? Which pieces of your registry hive files? Which bits of your browser cache?

Re: Where's my petabyte disk drive?

#45
post #35
post #23

Earlier quoted context omitted.

"in the early 1990s you could read hard drive content pretty easily with a scanning probe microscope" I believe that is an urban legend. http://all.net/ForensicsPapers/2012-12-07-OverwrittenMagneti... describes attempts to track down such cases: > To date I have found no example of any instance in which digital data recorded on a hard disk drive and subsequently overwritten was recovered from such a drive since 1985,…

Parent said reading a drive:s current data is possible. You said that reading erased data is impossible.

You're wrong.

> if you looked close you might find the edges of bits that had been written before and weren't perfectly aligned.

GGP spoke about both recovering data that had been overwritten and re-assembling data from destroyed platters without the original drive mechanism.

Re: Where's my petabyte disk drive?

#46
post #9

Massive hard drives only useful for archival purposes, under this argument: if your hard drive is being used for live queries, you want to access all the data on it. Even if you have have all the pieces in place to stream 1gig per sec off of the drive, a 1pb drive would still take 1 million seconds = ~11.5 days to read. So in practice in production it's more useful to have smaller hard drives in more places to work o…

I seem to recall reading some worries that current sizes are already pushing the limits of RAID setups. This in that it takes so much time to rebuild a drive given current interfaces that you risk one of the others in the array to fail during the process, thus making recovery impossible.

Re: Where's my petabyte disk drive?

#47
post #9

Massive hard drives only useful for archival purposes, under this argument: if your hard drive is being used for live queries, you want to access all the data on it. Even if you have have all the pieces in place to stream 1gig per sec off of the drive, a 1pb drive would still take 1 million seconds = ~11.5 days to read. So in practice in production it's more useful to have smaller hard drives in more places to work o…

on one of our production servers we have about 60tb spread across 240/250g drives.

Re: Where's my petabyte disk drive?

#48
post #43
post #39

Earlier quoted context omitted.

I don't think statistics will make better predictions than I can. For example, consider a moderately large file (eg. 100MB), which is only ever read occasionally, by sequential low speed streaming. It seems reasonable to place it on the HD, but it's music, and I want it on the SSD so I can have the HD powered down for lower background noise when I'm listening to it. And I could have another almost identical file whic…

I'd assert that it could make a better prediction for the majority of the files stored on your drive. For example, even if it was technically feasable to do with separate drives, do you know which files in the global assembly cache should go on SSD versus HD? Which pieces of your registry hive files? Which bits of your browser cache?

I don't use Windows so I don't have GAC or registry files. Browser cache always goes on the SSD because it's highly latency sensitive.

Re: Where's my petabyte disk drive?

#50

He is wrong about 6TB being the biggest hard drive in the market. Now that SSDs have become the standard they are taking up the curve. Samsung announced a 16TB SSD last year. I don't expect people to devote as much effort to making spinning disks bigger. http://arstechnica.com/gadgets/2015/08/samsung-unveils-2-5-i...

It does seem like in the long run, SSDs will probably be cheaper to manufacture than spinning disks?
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