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Why SSDs Won't Replace Hard Drives
storagedude writes "Flash drive capacities have been expanding dramatically in recent years, but this article says that's about to change, in part because of the limits of current lithography technology. Meanwhile, disk drive densities will continue to grow, which the author says will mean many years before solid state drives replace hard drives — if they ever do. From the article: 'The bottom line is that there are limits to how small things can get with current technology. Flash densities are going to have data density growth problems, just as other storage technologies have had over the last 30 years. This should surprise no one. And the lithography problem for flash doesn't end there. Jeff Layton, Enterprise Technologist for HPC at Dell, notes that as lithography gets smaller, NAND has more and more troubles — the voltages don't decrease, so the probability of causing an accidental data corruption of a neighboring NAND goes up. "So at some point, you just can't reduce the size and hope to not have data corruption," notes Layton.'"
Was plenty for my needs and boots Ubuntu in 20 seconds. Barely uses power when not in use. I'm a believer.
SSDs already leverage extreme parallelism via 15+ different channels, indeed they have to due to how slow most NAND chips (especially MLC) are. Eventually you're forced to the PCIe bus, especially as you approach 18-25 channels (FusionIO) and the SATA bus becomes a bottleneck.
@ article, yeah right but strangely enough all the HDD for the OS have been replaced the minute i could afford them
I'm in agreement with this except holographic storage has a few major drawbacks. Although SSD is steller for smaller storage requirements, platter drives are just too slow to be of much more use. Some highlights for holographic storage that should be pointed out first:
The theoretical limits for the storage density of this technique is approximately several tens of Terabytes (1 terabyte = 1024 gigabytes) per cubic centimeter
Another factor: photographic media has the longest proven lifespan - over a century - of any modern media. Since there’s no physical contact you can read the media millions of times with no degradation.
Unfortunately, the current limitations make this a far off product that probably won't see the light of day for many years.
The initial prototype was only capable of 20 MB/sec. Although this isn't horrible for optical storage, it's hardly a top performer
Although the theoretical limits are almost infinite, the reality of the prototypes were only about 300 MB. They have already fallen behind platter based storage.
Seek times were in the area of 200 ms, which is also pretty poor compared to platter storage.
With all of that said, there have been viable advances in holographic storage. HVD's (Holographic Versatile Disc) show true promise.
Ref: http://en.wikipedia.org/wiki/Holographic_Versatile_Disc
SSDs already do things now that HDDs could never do - like provide sufficient capacity, I/Os per second and low enough latency to satisfy the I/O needs of a maxed out virtual host with internal storage, or a virtual host for VDI. In a next-gen SAN like the WhipTail they beat $1/IOPS, which is necessary for making VDI cost effective. They do it with a power to IOPS ratio that's so superior it's not even directly comparable, in a form factor that's like comparing a toaster to a refrigerator.
Performance against spinning rust was beat off the line. Storage capacity is almost beat already (400GB SFF SSD, 1TB LFF), and the only reason it isn't flat beat is because the engineers rebel against storage media that's capable of oversaturating its connection bandwidth by such a large factor - they CAN put that many chips in that box but the idea is offensive. The only issue left of the big three is price. Prices of SSDs are coming down faster than HDD prices so the trend is clear. SSDs will replace spinning drives on more and more applications. You can plot an intersect if you want - I'm pretty sure that against enterprise spinning disk the intersect is less than the five years out stated in the article. SSD is the new tape.
And that's without considering those impossible technological evolutions explored in your post and elsewhere in the thread.
Help stamp out iliturcy.