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SSDs vs. Hard Drives In Value Comparison
EconolineCrush writes "SSDs hardly offer compelling value on the cost-per-gigabyte basis. But what if one considers performance per dollar? This article takes a closer look at the value proposition offered by today's most common SSDs, mixing raw performance data with each drive's cost, both per gigabyte and as a component of a complete system. A dozen SSD configurations are compared, and results from a collection of mechanical hard drives provide additional context. The data are laid out in detailed scatter plots clearly illustrating the most favorable intersections of price and performance, and you might be surprised to see just how well the SSDs fare versus traditional hard drives. A few of the SSDs offer much better value than their solid-state competitors, too."
I don't know about the cost/benefit for most people, but we're all running SSDs for our laptops now, and it's definitely worth it.
Once I realized that I could fit on a 64GB SSD comfortably if I didn't keep my ENTIRE photo collection on my laptop, it was a pretty easy decision to make to try them.
And after some testing, I've decided that it's enough worth it for us that we're all using them. In most cases it isn't a bit noticeable difference. But for some things it really does make a difference, and not having to wait for them is a big gain. The things that are a lot faster are: booting (rarely, but you're entirely "down" while doing it), opening big apps like OpenOffice, re-opening firefox or thunderbird when they flake out, and doing big find/grep jobs. Searching through e-mail and the like? Great.
For a long time, CPU increases were way outpacing the disc performance gains. We how have CPUs that are faster than most of my staff can really take advantage of on our laptops. But disc performance, even at 7200 RPM, was often the bottleneck.
So, we've traded volume for performance, and been very happy with it.
Longevity and reliability are tough to quantify, because for the vast majority of users the median SSD or disk drive will never fail as long as they use it.
Failures of disks occur at the tail end. Perhaps 10% of disk drives and 1% of SSDs fail over two years, but how do you compare them? Do you say the disk is 9% worse, or 10x worse?
Thats because the write-cycle limitation is pretty much a moot point these days. Considering the better reliability of flash memory, coupled with better wear leveling, reserved space, etc it takes a hell of a lot of writing to use up that life span. The thing is, drives that are very heavily written to tend to also need tons of storage (such as A/V editing)...much more than would be economical in SSDs. So the systems which would likely have a chance at wearing out an SSD are also usually the systems that cannot realistically use an SSD for data storage. At the moment (current cost of SSDs), the problem sort of solves itself.
While a pretty comprehensive article, nowhere do they actually talk about reliablity and longevity of these drives in their value calculations. That's a pretty important factor for me, and has been one of the reasons (besides price) that I haven't seriously considered one yet.
Honestly? No.
I recently replaced a less than 1 year old (failing) HD with a SSD in one of my servers. I expect my HDs to fail. I expect my SSD to fail. I put the SSD in instead of just another HD because it was a (relatively) cheap way to increase the performance of the machine significantly. If it lives for 1 year before failing, its doing better than the HD it replaced -even if it doesn't, the performance boost is worth it.
"You want to know how to help your kids? Leave them the fuck alone." -George Carlin
I've seen, and have been able to reproduce reliably, hard disks losing their internal cache data, claiming to have written it to platter when in fact it was not. And I am /not/ talking about battery-backed RAID cache, OS write cache, or anything of that nature; I am speaking specifically of the internal hard disk cache.
When we figured out what was going on, needless to say we were all a bit shaken. But the lesson is learned: your storage needs to have a battery backup system.
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About 5 months ago I bought a $700 250G SSD for my laptop and ditched the spinning disk. The system is overall faster, and for someone who's used HDs since the 286 days and floppies before then, the performance is oddly different (almost always better). The big bonus though is that my laptop takes about 10 seconds to boot (once past the BIOS) while it used to take about a minute. This has changed the way I use my computer, and is enough to justify the swap. I do have a few other systems I occasionally use, and apart from the OLPC XO-1 (which has its own performance characteristics that are different again from anything else I've seen), it's now kind of irritating to use spinning disks and feel those delays again. As the costs go down, I imagine anyone who's tasted SSDs will spread the technology very broadly among their friends.
For every problem, there is at least one solution that is simple, neat, and wrong.
because for the vast majority of users the median SSD or disk drive will never fail as long as they use it.
Bwahaha, right. Have you known many people using SSD's? I do and they have an extremely high failure rate. Currently much higher than the old spinning media. Most last less than 6 months. The oldest SSD I know of lasted 2 years. I know of no SSD that lasted longer than that.
I'll stick with hard-drives until that improves significantly.
And as for value, a good 128GB SSD is $300. For about $200 more, you can get 3 x 150GB Raptors and a $100 Adaptec SATA RAID controller, config it in RAID 5 and get comparable performance, not to mention a little redundancy. The extra initial investement will pay for itself in uptime over the long-term.
I'm sorry, but you're completely and hopelessly wrong. Spinning rust gets around 100 IOPS, maybe 200 at 15k RPM. The Intel X25-E gets around 10,000 IOPS. Assuming linear speedup (which you won't get anything close to), you'd need 100 rotational drives to come close to the performance of a single X25-E.
The only performance metric where SSDs and spinning rust are anywhere close is on linear read/write speeds. Sadly, that's of no consequence, because that workload only exists in benchmarks.
(Also, god help you if you put a database server on RAID 5... goodbye performance! RAID 10 or bust.)
Game! - Where the stick is mightier than the sword!
high altitude computing. I was reading an article about mountaineers with laptops, when you get up around 15 or 16 thousand feet the air pressure is so low that the Bernoulli effect no longer works properly in your hard drive, so your drive makes lots of nasty noise and is more prone to failure. With SSDs you just have to worry about the lack of oxygen damaging your brain and your internal organs, but not about endangering your data or the performance of your laptop.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
What about databases? I have a project based around a PostgreSQL database and it's pretty intensive. The bottleneck on the database's performance remains the disk I/O. A good SSD, I estimate, would provide a very noticeable boost to this. Note the system is about equal parts writing to and reading from (well, about 30/70) which is the worst of all worlds for a database.
Aide-toi, le Ciel t'aidera - Jeanne D'Arc.
The GP might have missed the point, but you certainly did. Let me put it more bluntly: Comparing the price of an ssd to a disk by $/GB is idiotic, and there is exactly as much point in it as comparing the price of your processor to the price of your ram by $/MB (looking at the size of the cache). His point wasn't that you get better $/GB in a smaller ssd -- it was that the very metric of $/GB is completely and utterly stupid when evaluating the usefulness of an ssd as an upgrade.
A SSD is not an upgrade that buys you more space. It's an upgrade that makes your computer faster. In that, practically all of them are great value; for normal desktop use I'd much rather have an Intel ssd and the crappiest still-in-production dualcore from AMD than no ssd and the most expensive available quadcore from Intel. And I have actually used both kinds of systems. That is how awesome the difference is.
(well, the high-end Intel rig was actually a mid-range i7, but it was overclocked way past any of the models they sell.)