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Hybrid Hard Drives Just Need 8GB of NAND
judgecorp writes "Research from Seagate suggests that hybrid hard drives in general use are virtually as good as solid state drives if they have just 8GB of solid state memory. The research found that normal office computers, not running data-centric applications, access just 9.58GB of unique data per day. 8GB is enough to store most of that, and results in a drive which is far cheaper than an all-Flash device. Seagate is confident enough to ease off on efforts to get data off hard drives quickly, and rely on cacheing instead. It will cease production of 7200 RPM laptop drives at the end of 2013, and just make models running at 5400 RPM."
No chance this is just the company saying this because they missed the boat on solid state drives?
SSHDs as implemented by Seagate do not require any support whatsoever in the host. Their caching algorithm does not care anything about the FS. It is block level. I have one working just fine in arch linux. Linux just sees it as any other HD, only it is much faster overall. Obviously you will never see any improvement at all in huge file copies.
WD has some lame Windows-only SSHD tech that does require special software on the host.
I truly doubt that anyone working at EA plays their games.
If you don't have most of your stuff stored via a library or other link on an NSA or server . . .
Wait a sec . . . How do you access all of your data at the NSA? do they offer a subscription service or something?
I have the suspicion that Seagate is planning quite specifically; but just don't care all that much.
The majority of orders will, presumably, be from OEMs looking to stuff HDD slots on the cheap, while still complying with the Win8 hardware certification requirements(most notably, resume in under 2 seconds) and possibly Intel's "ultrabook" requirements, which have their own I/O demands.
I suspect that Seagate's calculations of 'How cheaply can we build a drive that will satisfy the letter of the requirements that our customers need to meet?" were made with care, and aren't crap at all. They're just something of a lie if you expect that level of performance to be maintained under more stressful loads.
I purchased one of those drives on the day it was available at Newegg for use in Linux, and then shortly after for a pair of them in RAID0 for a desktop (gaming) system where data integrity wasn't my main concern. In both systems I ran into firmware problems and could not natively flash them in the system that was running them. I pulled them into a bench PC I have and flashed them there and everything was fine. The issue had to do with power saving and would cause some pretty frequent hardware locking issues on both systems that was painful until I was able to resolve them. All 3 of the drives are benched now, but still work fine. I never lost any data due to the lockups - they would just hard lock the PC for a second or three and then continue working like nothing had happened.
In my experience this is typical early adopter fare.
"Back in your day to load each webpage, did they deliver each bit by abacus via horseback?"
Isn't that how YouTube does it since Google bought them?
Which for most users and usage scenarios, is basically forever. There's been a volunteer-run test of longevity which stresses an SSD until it fails by writing data to it continually. And the SMART data typically gives you plenty of advance warning - the Media Wear Indicator (MWI) tells you how many cycles are left in the array - once it hits zero, it means the number of write-erase cycles has hit the guaranteed limit and you're running in unknown territory (though there are usually still spare blocks and most will still have plenty of life). If you want guarantees, once the MWI hits zero, it's time to back up and get a new SSD. The tests run until the drive itself dies which tell you how long you have left. So you generally have a LONG indication of media wear out.
However, the biggest problem SSDs face is actually sudden loss and corruption of the FTL tables (the ones that map logical sectors to actual flash sectors). If you hear of SSDs dying prematurely, it's almost always because of table corruption. These tables contain things like sector translation, sector wear, dirty/clean bits, trim status, etc.
In the past, you could regenerate the tables from the spare area data (typically 16 bytes per 512 byte data area), but use of enhanced ECC algorithms consume that space up to accommodate better error handling. Plus it also meant way longer mount times as the controller had to scan the entire media for the information (many seconds long).
These days, controllers come with 512MB or more of RAM to hold the tables in memory for quick access. The problem is the tables are often written out lazily to storage, which means if you yank the power suddenly, the SSD might not be able to write the dirty data to stable media, or worse yet, it'll be in the middle of the write operation which leaves data in an unknown state.
Good SSDs often have piles of capacitors to serve as emergency power which can keep the array powered for a couple of seconds - more than enough time to flush the tables to storage and protect your data. Of course, this costs a lot more money and is usually present only in the top tier drives and enterprise class SSDs. If an SSD dies suddenly, it's usually because of this.
Hard drives use the back EMF produced by the spinning platters to perform emergency shutdown procedures, including retracting the heads.
Fumble fingers - meant to type NAS.
Sure you did.
I took into account cost, capacity and performance when choosing the drives.
But not battery life, apparently, which is the one area where 5400 rpm drives beat out 7200 rpm drives, and is possibly the reason they even exist. A 5400rpm hybrid would need to spin up even less and should do even better on the battery front. Not to mention that if you get a cache hit, it doesn't have to spin up at all, which is a big performance boost too.
So while "benchmark" performance might not be great, real world use might be substantial; as the hard drive could spin down more, and you could access the drive without spinning it up some of the time, possibly even most of the time.
There's definitely potential to be both markedly faster in real world laptop use scenarios and consume less battery with a hybrid. Whether that pans out in reality I don't know.