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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?
This looks like Seagate desperately clinging to their old bastion. Even Western Digital bit the bullet and started working on pure SSDs. The problem with Seagate's calculations is that there'll come a time (not that far into the future) where NAND will be cheap enough to get a full SSD for only a moderate price hike over a HDD, all while getting all the benefits of a pure SSD drive. They risk getting left behind by clinging to the hybrid drive idea.
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've used an SSD. Works great for my laptop and router, don't care for it for my desktop largely due to price. For $60, I can get an 80GB SSD or I can get a 2TB HDD. That 80GB SSD is going to require an additional HDD anyway for storage for many people.
Most consumers are still going to go with cheapest and, outside of the tech-oriented crowd, don't really care if they have to wait an extra few seconds. As far as I'm concerned, the SSD boat is still boarding passengers and is no where close to leaving just yet. Once SSD prices are more competitive with hard drives (which could be another decade or two at the least), then you can say that ship has sailed. Until then, cost will trump performance for the largest markets.
The lifespan issue with SSDs has three main factors.
1: Type of flash memory (SLC, MLC, TLC, in order of decreasing durability)
2: Size of the flash drive (larger drives have more room for wear leveling algorithms to work with, thus staving off flash cell burnouts due to exceeding maximum number of writes).
3: The amount of throughput on the flash drive. An expected heavy load is roughly 10GB/day. Doubling the load halves the lifetime of the drive. Quadrupling the load quarters it.
Granted, the cache on a Hybrid is being used a bit differently than how you would use a straight SSD. But, with such a small cache drive, you ARE going to wind up cooking it after a relatively brief period of time.
Chas - The one, the only.
THANK GOD!!!
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.