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Notebook Storage SSDs and HDs Compared
The Raindog sends us a particularly timely showdown article comparing seven 2.5" mobile hard drives, four of them HDs and three SSDs, across a wide range of application, file-copy, power-consumption, and noise-level tests. Tom's Hardware was recently forced to issue a correction to a claim, which we discussed here, that SSDs aren't actually much more power-thrifty than HDs. The Tech Report's in-depth comparison provides some data points on the question of whether solid-state storage is ready to supplant traditional mechanical hard drives, but notes that the price disparity is still substantial.
It's the lack of moving parts. Try dropping both types repeatedly and see which one stops working first.
http://twitter.com/OLDTELEGRAM
I think someone forgot a critical link... try this for the Tech Report article:
http://techreport.com/articles.x/15079
I've read that the algorithms used in SSD's are usually proprietary. The problem with SSD's is that they DIDN'T fix the wear leveling problem. It exists, just a lot slower now due to the algorithms referenced above. If my drive dies, I'll have to find a service that can recover my files, but they will have to be certified in samsung, seagate, white label, etc. I really feel uncomfortable with that idea.
Restore the madness of youth's lechery
Boils down to a couple of things: Reliability = Good, Speed = Good, Space = Fair , Cost = Why can't I pirate this! Damn, but that would be "stealing". When the cost goes down and the size comes up a bit, Ill be ready to buy one.
"It's ok, I'm completely secure as long as my iron is off"
Nobody reads them anyway, so apparently the editors have decided not to bother including links anymore.
You're missing SLC vs. MLC and high-performance controllers.
I would love an SSD for r/w performance that blows a mechanical drive out of the water.
I would love an SSD that doesn't use much power.
I would love an SSD that's shockproof.
I would love an SSD that runs cool.
I would love an SSD that's silent.
I would love an SSD that roughly the same price performance of a mechanical drive.
The problem is, it can't be all of those things. It can't even be most of those things. So pick the ones you need.
And high quality tested parts. At least that was what I read in an article by someone that checked if the SSD drives were ready for deployment in his server farm. These guys like to do rigorous testing and good information, at least the professional ones.
Don't forget that these controllers are brand spanking new, and they are not in their 1000th revision like the controllers used on the hard drives. I'm really looking forward to the Intel designed drives. I presume that they will use their own controllers - the first showings seem to be very positive (no numbers posted yet).
I thought modern, high density flash memory had only a ~3000 cycle life. The old, single bit/gate memory was good for 100,000 write cycles, but I think those parts topped out at a few megabytes.
Single-level-cell NAND flash is still produced, for use in the faster, (slightly) more expensive drives with longer warranties. And multi-level-cell NAND flash is usually guaranteed for 10,000 writes, not 3,000. And the number quoted on the data sheet is the minimum longevity for each sector; more writes than that are possible. The CF controller doesn't retire a sector until it starts returning too many just-barely-correctable errors.
The thumb drive will die young if you use it as a hard drive, they're typically only designed for 10-15k write cycles (per cell). They also use MLC cells, which store two bits each - that doubles the capacity, but quadruples the error rate. Errors are usually corrected via parity/ECC, but obviously if you have more errors, you're more likely to exceed the ECC threshold.
There's also the issue with performance. A thumb drive might get 10-15mb/sec on a good day, 20 if you pay way too much money for a "dual channel" unit. Hard drives are expected to deliver 40mb/sec minimum these days, else your apps will take forever to load.
If you really want to be a wacko, you could try RAID-0 across a bunch of thumb drives. You'll get the performance back, but good god you're playing with fire.
-Billco, Fnarg.com
SSDs are the best thing to happen to PCs since the invention of the mouse.
I have had a MemoRight GT for 3 months now, and my laptop feels amazing. I am disappointed Tom didn't include one in his review.
Because the seek speed is 40x + than an HDD, data access is blazing fast on even the cheaper SSDs. The hangup is in the slow read/write speeds and problems with random access. MemoRight GT is the first SSD I saw that was faster than HDDs in all of these areas, and hence it not only outperforms I/O wise, you get the full benefit of fast access... And this will make your PC feel 4x faster.
Everything becomes faster. Web pages load faster. Email arrives faster. Windows moves faster. No more HDD cache writing lag or "what is my HDD doing" moments.
I don't care that much for battery life, though I am sure some do. As Tom concludes, that is pretty much a spec you just need to look out for, so if you want it, look for a drive that has it.
What I do love though is the silence. Anyone who has gone through an HDD failure is sensitive to HDD sounds probably more than they know, or would like.
SSDs make no sound, and there are no strange vibrations.
I spent close to 2K on the drive, but it was worth every penny. If I buy a new SSD when the 3rd generation drives arrive, my Memoright will still always have a place in one of my notebooks.
And how many users will write over 320 terrabytes to their hard drive during it's lifetime? That's 190 days of continuous writing at 20MByte/sec. I wish people would stop citing write cycle limits, I have yet to hear from anyone who's actually failed a drive this way.
It's called... wear leveling algorithms.
The future is actually probably going to be a hybrid of SLC and MLC. I read a paper recently on this. They got about the same performance as SLC only, using only a small amount of SLC.
Unfortunately, they're not very _big_. 32 Gig for a hard drive is fairly pitiful these days: the hard drives stacked against SSD in Tom's Hardware's article were typically 10 times the disk size. So our soldier boy in the story above, where they had 200 movies they lost in an attack on their campsite, would have had to have 10 times as many drives. The power savings and stability are great for small scenarios and high availability resources, such as laptop drives or small, encrypted filesystems. But for overall storage, having to pay the power, cooling, and space cost of _10_ drives rather than a single hard drive makes no sense.
But my goodness, that OCZ brand drive blew the others out of the water in the tests, didn't it? I'm very glad they added it to their tests so that I know about it for reference on future projects. _WOW_, that's a good drive!