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Samsung Mass Produces Fast 256GB SSDs
Lucas123 writes "Samsung said it's now mass producing a 256GB solid state disk that it says has sequential read/write rates of 220MB/sec and 200/MBsec, respectively. Samsung said it focused on narrowing the disparity of read/write rates on its SSD drive with this model by interleaving NAND flash chips using eight channels, the same way Intel boosts its X25 SSD. The drive doubles the performance of Samsung's previous 64GB and 128GB SSDs. 'The 256GB SSD launches applications 10 times faster than the fastest 7200rpm notebook HDD,' Samsung said in a statement."
So it launches applications 10 times faster [sic] (should say in 1/10 the amount of time), but the article only claims speed improvements of about 3.5 to 1. People need to seriously examine how they quote or accept statistics.
Jim Elliott, vice president of memory marketing at Samsung, said the new 256GB drive can store 25 high-definition movies taking up 10GB of space each in just 21 minutes, which he said is a significant advancement over a 7200rpm hard disk drive, which takes about 70 minutes.
Ah yes, but you don't have the seek times of the 7200rpm drive which are at best ~7ms. And since opening an application involves opening lots of different files (in different physical locations on the drive), this is where launching an app can be 10x faster.
So for straight writing a single, large, contiguous piece of data, it's only 3.5 times faster. For loading 200 random, tiny files, it's ten times faster.
Me neither. We spent weeks (which translates to tens of thousands of dollars) benchmarking and optimizing a database app. The thought of accelerating it by a factor of 5-10x with a simple hardware upgrade is stunning.
1 TB of SSD today = 17 * $150 = $2,550.
1 TB conventional storage = $95.
SSDs are still over 25 times as expensive. They will improve quickly, but they need to hit a moving target to kill conventional drives.
For comparison, an Imation 128GB costs between $1,900 and $2,500.
I'd guess that the Samsung 256GB ones would therefore cost in the range of $5,000 +/- $2,000 (probably more likely +, given there's usually a premium for new and for bigger).
Wonder how many hours this drive would last if used for swap or a database container until the flash cells wear out and start returning errors.
10k*256GB / 200MB/s write speed = 151 days at full write 24/7. And you'll probably get some nice warnings without data loss since the typical failure mode is that they can be read but no longer written. Of course if you're using swap even nearly that much, you're doing it wrong. I'd be very surprised if my swap use exceeded 10GB/day, in which case it'll take me some 700 years to hit the write limit. And if you're running a heavy database there are drives for you, just not this one. So who do you work for? Western Digital? I think they're the only ones that haven't realized the boat is leaving and they're lost in the mountains.
Live today, because you never know what tomorrow brings
You can get 16GB SDHC cards for about 30 USD. Those are class 6, which means you get anything from about 8MB/s to 20MB/s depending on the brand. Of course, if you want more speed, you can always use RAID0.
In fact, given how cheap they are, a RAID5 system would probably make sense. You get a speed boost, and the ability to hot swap a single card if it goes bad. ZFS would also work really well, but I don't know if you'd get a speed boost that way. Also, all these approaches would allow you to very easily extend your system by buying another card (and reader) and adding it to the pool. (You may want to check up on whether you can remove it again later, though.)
Hmm. Thanks for prompting me to go and look at this stuff. I might actually do this for my next lightweight server.
http://tinyurl.com/cheapssd
Probably nothing like a Seagate, but, technically they are SSD drives. I imagine they are probably more like big thumbdrives with a run-of-the-mill SATA controller slapped on them.
Mir tut es leid, Menschen daß Einfältigfehlersuchenbaumfolgendenaffen sind.
Those are MLC flash, random writes are going to be horribly slow and will reduce the wear life to months in a server application. Would be perfectly usable in a netbook/laptop application though.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Giga is an SI prefix. It is defined as 10^9 and abbreviated as a capital G. So to say you have 200G of something implies you have 200,000,000,000 of them.
Computers do it wrong. When computers say Giga they mean 2^30, not 10^9. That's wrong, for that you use IEC prefix of gibi, abbreviated as Gi.
The reason is that back in the day, computers had little memory. Thousands of bytes was all. So when talking about thousands of bytes, programmers started calling them "kilobytes". After all, it is close. 2^10 is close to 10^3, only 2.4% error. Well memory kept growing, and the incorrect prefix usage kept going on and they kept using bigger ones.
However this has two problems:
1) The error grows. At the giga level it is about 7% off. The large you are talking about, the more the difference between the base 10 prefix and it's "closest" base-2 amount.
2) You get confusion between levels. For example suppose your computer shows you something in megabytes. It says you have a file that is 2000 megabytes. Well that's 2 gigabytes right? Wrong, 2 gigabytes is 2048 megabytes. So it is rather unintuitive to humans. We work in base 10, the numbers displayed are base 10, but the prefixes are used wrong.
Really, the harddrive makers are right. Computers should display amounts according to the base 10 prefixes. Computers have no problems with base conversions, they should be doing that for people.
That didn't last all that long though. I went from cassettes in a TI 99/4A in 1984 to 5.25" diskettes for the Apple ][ machines at school from 1986-1988. By the time I got to college the 3.5" disks were starting to come out and this trick didn't work on them.
There were always rumors that treating your disks like this would shorten the life of your diskettes or your disk drive itself, but we always chalked that up to a conspiracy by the media manufacturers. Certainly my 5.25" disks lasted well beyond the point where there were drives to read them anymore. I never heard about anyone having to replace a drive because of it either.
Anywhoo what were we talking about again? The important thing was that I was wearing an onion on my belt, which was the fashion at the time...
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
This TinyURL redirects to:
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&SubCategory=636&N=2013240636
Actually there is a row access time which can be quite high, as high as .5ms for MLC which compares with 2.5ms for 15k rpm drives. Add to that the relativly low IOPS for MLC (less than 100 according to this review using the database server IOMeter profile which is 70/30 read write if I remember correctly) and for a server load they lose bigtime to drives considering they get worse performance, have significantly lower MTBF, and have way less GB/$. SLC is a bit harder to quantify as the best units have MUCH higher IOPS per unit than disk so you have to figure out how much capacity you need and how reliable you want it to be as well as how much power budget you have.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
One problem is they write in blocks (128kb?) and the entire block needs to be erased to modify a single byte.
That chews those writes faster than you'd expect, and write leveling can only do so much especially if the drive is mostly full.
Calibrated motor? You think that they have to specially make motors which run at exactly 7,200rpm? O_o
They just use a feedback mechanism for precise positioning and speed.
Flash on the other hand chews up massive amounts of space on silicon.
That is quite expensive.
SSD = 220MB/s transfer rate
DDR2 800 RAM = 6400MB/s transfer rate (peak theoretical)
Nope.
Just disrupt the deflector shield with a tachyon burst.
Not at all. Solid state drives are still orders of magnitude slower than RAM (i.e. main memory).
No, you wouldn't necessarily expect to be able to load 3000 tons. Firstly, what type of tonnage are you talking about? In shipping, there are several different types of tonnage, or in other words, different values for the same thing, with at best slightly different names. For example, Gross Register Tonnage, Net Tonnage, Gross Tonnage, Thames tonnage, Panama Canal tonnage, Net Register Tonnage, and who knows what else.
Secondly, suppose a ship has a "capacity of 3000 tons". Could you fit more pillows or gold bars into the ship? Which one will fill the hold first? Can you fit 3000 tons of pillows into a ship with a capacity of 3000 tons? Can you fit 3000 tons of helium in? 3000 tons of depleted uranium? What if the ship is to be sailed from a salt water port into a freshwater lake? Does that affect anything?
Why would you pick tonnage of shipping as an example of regular math? Shipping measurements are all over the place. For example, how long is a ship? Well it depends on the shape of the ship, and where you measure it. Length at the waterline or length overall? With the ship loaded or empty? Heeling or sitting level? Salt water or fresh?
Just about everything to do with computers is simpler and more regular than just about anything related to boating.
Don't think so
DLT Tapes ($25 for 40 GB + cost of drive) are now more expensive than hard drives.
They are even deader than spinning disk.
Reads are byte word size
The caveat is that it is necessary to erase the whole block to write a byte when a bit needs to be changed from its erase state. e.g. :
If the erase state is 0 and a bit needs to be cleared (it holds a 1 in or scenario, and we want it to be zero) then it is necessary to erase the whole block. This (obviously) means copying the block contents to RAM, zeroing the FLASH page in which the byte resides, and then writing the page back to FLASH. It sounds worse than it is, and ultimately the overhead doesn't put a dent in the difference between using spinning media and FLASH. For example, what is the overhead to change a single byte on a hard disk?
Update the metadata (itemization of steps not included; you get the idea.)
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
Good god, man, only suckers with corporate accounts have to shop at CDW. $1,900 for an MLC drive? Try $300 for the same speed specs. If you want SLC you'll have to double that, but still, CDW is way overpriced these days.
Seek time is next to zero for SSD drives (less than 1ms). There's no seeking because it's all in the register already.
I'm a writer, a poet, a genius, I know it. I don't buy software, I grow it.
One thing to remember is people like my parents and grandparents. I use over a TB of HD space. My parents haven't even used over 50 yet, and my grandparents even less.
Due to the mechanical components of hard drives, they aren't going to get much cheaper, even/especially in bulk - some of the bottom end we see are the manufacturers putting their old drives on fire sale.
Once the manufacturers can get a 40-80GB HD for LESS than they can get a hd*, I predict they'll start switching. They're already on the poor side for GB per $.
The cheapest laptop HD on newegg is $50 for 80GB(.625). Lots of 320GB($70,.22), 500GB($110,.22). The cheapest 3.5" HD is $36 for 80GB(.45). $42 for 160GB(.26). A 1TB one runs $95(.095), so per GB it's a much better deal, delivering 4 times the GB per dollar over the 'cheap' 80GB. The cheapest SSD is $20 for 4GB(5). Not very efficient, not even very fast. Going up - $145 for 64GB(2.27). $278 for 128GB(2.17) Not much economy of scale gained, but that's to be expected. 32GB seems to be where the SSDs start flattening out($84,32GB,2.63) at the moment.
Going by this - I figure 3 years before you start seriously seeing SSDs replacing hard drives in laptops - and it'll start on the low ends for cost savings, and the high end for performance.
It'll be another 5-10 before they start doing the same to desktops. Still, I figure upgrading will become common again - fast flash for OS and programs, cheap big HD for most multimedia.
*As long as it can be expected to last long enough that they don't have to do warranty work, and performs at least as well.
I don't read AC A human right
SSDs do not allow you to directly read/write/erase flash memory. The firmware includes a flash translation layer that lets the host read/write 512 byte sectors just like any other drive. Sectors do *not* have a fixed location on the disk. Writing a sector simply appends it to the current erase block, and updates the translation table (also an append). When it runs out of blank blocks, it picks one to erase based on its wear leveling algorithm and garbage collection, and copies any live sectors to a fresh erase block. Just like a HDD, there are plenty of spare erase blocks, which are needed for the copying garbage collection and for when erase blocks go bad.
While the basic function of FTL is open, the wear leveling and garbage collection algorithms are fiercely proprietary. (The best ones actually count how many times a block has been erased and keep the counts even - and do this at high data rates.) This is OK for now because there is also fierce competition, and the code runs only in firmware on the device - not on the host. (Same as the controller code on a HDD.) Should the SSD market ever shake out into a monopoly, the basic FTL ideas are available.
I've found that for VMs it's best to short stroke the drive. Partition it so that your VMs are in the middle of the drive, all together, in a somewhat narrow section of the disk. That way, even while doing high IO/sec, you're at most half a disk seek from anything else on the disk. Also, always pre-allocate your VM disks; the performance difference is huge. If you're running a *nix distro, it pays to put your swap on one side of the VM partition and /var on the other, this way you shouldn't have to stray out of the center of the disk too much. The anticipatory IO scheduler in Linux helps a good deal here, you'll get much more throughput for a sub millisecond latency cost. With NCQ/NTQ, and only using 1/3 of the disk surface, you can feel the difference... especially as compared to a single partition that's running low on space and doing a full stroke to get from the VM to your OS.
If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.
It seems (to me anyway) that people dont think a single byte being defective is a big deal, when in fact its dead blocks which are somewhat larger.
Logs, most databases and many other things have frequent small writes.
It means that the SSD can be fried somewhat faster than people think.
Wear leveling just means it all fails at the same time instead of some bits failing sooner than others.