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Seagate to Offer Solid State Drives in 2008
Lucas123 writes "Seagate will introduce drives based on flash memory in various storage capacities across its range of products including desktop and notebook PCs, according to Sumner Lemon at IDG News Service. The drives are expected to consume less power (longer battery life), offer faster data transfer rates and be more rugged than spinning disk, which has moving parts that can be damaged from an impact."
The rewrite issue has been rehashed a million times. It will be fine. I promise.
The headache now is that most file systems are optimised for mechanical based storage media so wont this also mean we will have to look at changing to new file systems ?
I think the 160 GB refers to the hybrid disks Seagate also has in their lineup (which are also mentioned in TFA). Would be more logical too because even with todays cheap flash prices, a 160 GB flash drive would still be relatively pricey.
Do the math. When rewrites were a problem, how big were the chips? How big are the chips now? How many more writes are possible now? The amount of data that becomes a problem is astronomical at this point...the 'rewrite problem' will kick in long after a spinning disk has found a reason to die.
Nerd rage is the funniest rage.
Nobody mentioned the noise! SSD's are silent.
I can't wait for ssd's. Every hard drive I've owned has been noisy and they drive me nuts.
As for durability... hrmm... maybe in its current state, flash doesn't last that long. But, the potential has got to be better than a constantly-spinning platter of disks. I've never had a RAM stick, or flash card die on me, but I've lost many hard drives.
Also, I think there may be greater potential for memory density. Spinning platters inevitably have wasted space, forming a cylinder in a rectangular prism.
I'd be interested to see the effect of SSD's on prices of normal hard drives. Normal HDD prices have been plummetting rapidly over the last couple of years - I wonder if the lure of flash will push them down further.
I think with capacity being so important, price/MB will be a big determining factor in getting flash into enterprise storage. I think the desktop, and (obviously) laptop markets will lap it up first.
Am I safe in assuming SATA transfer rates are sufficient to handle a SSD?
Will it move choke points elsewhere on the system?
I'd like to know what other practical benefits such would have other than lower power consumption and durability.
Someone hates these cans.
It's not all that bad. If I remember correctly, most flash memory can take 100,000-300,000.. according to wikipedia:
"while high endurance Flash storage is often marketed with endurance of 1-5 million write cycles"
I did a small research project (informational) on flash stuff recently for school, I believe solid state hard drives back in June or so were said to have about 2 million writes.
2 million writes per sector. You can always move the information around, and algorithms are being written to do that.
But, with all that, seems like hybrid drives would be the way to go right now.. after all, there's no limit on READING from solid state drives, just writing.
Not trolling, I just havent ever seen hard stats on current flash/solid state durability over time recently.
Take a 40GB hard drive, and pretend it's Flash memory. If you wrote 40GB worth of data to it every single day (with the circuitry inside a drive to spread writes out over cells evenly), then you would average 1 write per day across each cell. Flash memory can be written to a minimum of 10,000 times before dying, most is even more reliably by an order of magnitude (100,000 writes). Assuming we have crappy 10,000 write limits, we could write 40GB to the drive every day for 10,000 days, or 27 years, before failing is an issue.
Looking at the 40GB drive in one of my machines, the total writes in its uptime comes to about 800MB, which is a shade under 24 hours uptime. That's 800MB worth of writes in a day, 50 times *less* than writing 40GB to the drive every day, so a 40GB flash drive at my current usage rate could be expected to last 27 * 50, or 1350 years.
A lot longer than I have to worry about. The numbers are going to differ for some people, but the initial stats work out - few people would write to every cell every day, and even then that's decades worth of use.
I have been researching some of the more current SSD drives lately, and I know that they greatly improved the technology/algorithms behind how they write data to the physical memory. Most companies use some kind of wear-leveling techniques that evenly distribute the writes over the entire surface of the disk, maximizing the disk's life span. I have also read that the different-sized memory modules have different physical characteristics such that smaller modules are actually outlived by larger ones.
I can't give exact figures, but I've seen comparisons showing a reasonable life span (>20 years @ 100GB of writes/day) - some of the numbers are even comparable to those of spinning/mechanical hard drives. Considering how often mechanical hard drives seem to fail, it doesn't seem that there will be any major roadblocks in terms of reliability.
I know what I've written is mostly qualitative (apologies on that), but I know the research into how to mitigate the problem of life span has truly advanced in the last few years as interest in SSD has increased. Jim Gray of Microsoft Research fame, predicted that SSD would replace mechanical drives not far off from now. Check out his paper "Flash Disk Opportunity for Server-Applications" for more on that.
SixD
I'm not sure flash drives need to meet and exceed conventional drives in capacity (maybe that's why conventional drives have slowed in growth)? I like to use virtual machines for development, but never had the right medium to work on them, exchange them between developers, etc. They're just to big to swap easily by network, external hard drives are too big and fragile, etc. But now I see 16 GB usb flash drives are available, and only $130 to boot! I'm going to try installing a VM on one and buy a few more if it works well. 16 GB is PLENTY for installing a linux development environment, and I think for XP, too. Vista, I don't know.
All modern flash drives use write levelling to ensure writes
are evenly spread across the device.
This article
takes those numbers and using a hypothetical "write logger" app that
continually writes, estimates an average life of 51 years.
MTron specs for their SSDs estimate:
So lets lay this one to rest. SSDs are worth it.
I wonder to what extent current high capacity HDs owe their high power consumption to the needs of high performance (low access time and high bandwidth). But if a large flash cache (say 4-16 GB) buffers the HD, then the HD mechanism could be redesigned to a much lower spec. I'd bet that a ultraslow 300 RPM platter with a stepper-motor head (versus the 4200 to 7500 rpm platter + voice coil technology currently used) would provide adequate performance (and low power consumption) if flash handled the vast majority of accesses and high speed read-writes. The physical disk mechanism would only need to support a bandwidth of about 2-3 Mbytes/sec (for a sustained read of an HD video stream) and flash would provide the 80-150 MBytes/sec burst bandwidth to compete with current laptop drives. (Hardcore video editors wouldn't use this device, but then they wouldn't use most of the low-power laptops on the market anyway).
Two wrongs don't make a right, but three lefts do.
The drive controller will do wear leveling, so it will not rewrite the same bits over and over again, even if the OS thinks it does. This has also been rehashed a million times.
Relax, they still sell mechanical hard drives.
If we go back about 20 years, hard drives were for non-volatile fast-access storage, and tape drives were for backup, bulk data storage, archiving and sometimes data transfer (when there was too much for floppies.)
Now that flash is reaching the point where we can contemplate using it for the primary non-volatile storage niche, we may see hard drives being displaced into the backup/bulk storage/archiving niches. If so, expect to see increasing emphasis on ways to hot-plug hard drives into your computer, and increasing emphasis on price/GB and decreasing emphasis on performance and possibly per-drive capacity.
We'll really know we've reached this point when hard drives are used as a medium for delivering software.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
Guys, hate to break it to you, but anyone who wants to be running on solid state, is.
3 IDE-CF adapters cost me 8$ including shipment on ebay last week. My game box runs of a 16GB CF card (200$ - new - on ebay, available for months now) with vista (yes, vista on a 22MB/sec CF, though I've gotten it there via ghosting rather than via a regular install), and my living room PC runs XP off a 2GB CF card that cost about 25$ new (again, ebay price, store prices typically a tad higher).
Yes, 20MB/sec is less than the 50-70MB/sec read speed an average harddrive gives, but that is offset by near-zero seek times.
If under windows, make sure you turn off:
* SWAP
* ntfs Access time writes (fs tuning utility, one command from shell, or a reg key)
And if you want to be even more thorough and flash-friendly:
* 8_3 filename writes (in ntfs every file has two filenames one that is backwards-compatible to 8_3 naming. No need to waste CF writes on that)
* Any software that routinely writes stuff to disk.
If you're fanatic, do:
* Event logger
* Indexing
If you want >16GB, you can buy several, then use LVM/dynamic disk/multiple partitions depending on your OS to use that.
I just have the core 16GB (about 8GB occupied) on the game box, and do the rest of the storage (aka keep the Program Files directory) on the RAID5 fileserver over Gigabit LAN, which gives me about 40MB/sec read and write, which is IMHO sufficient. Were I not to rely on that, I'd get another two 16GB cards on a CF-IDE adapter, plonk a RAID0 on them and voilla (assuming you can get windows to make dynamic disks of removable storage, which the CF cards are still recognized as, even when on the IDE bus), which I am by no means certain.
If you're on Linux, no problem there. anything and verything can be raided and LVM'd at will.
A RAID0 of these would cost 400$, give 32GB and give about 40MB/sec performance.
So no need to get overly excited with SSD. They're just an overpriced nicely bundled version of what is already cheaply available, kinda like external harddrives. And they'll keep on being that for a while yet.
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It would be awesome. That's the point.
True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.