Intel X25-M SSD: Intel Delivers One of the World's Fastest Drives
by Anand Lal Shimpi on September 8, 2008 4:00 PM EST- Posted in
- Storage
How Long Will Intel's SSDs Last?
SSD lifespans are usually quantified in the number of erase/program cycles a block can go through before it is unusable, as I mentioned earlier it's generally 10,000 cycles for MLC flash and 100,000 cycles for SLC. Neither of these numbers are particularly user friendly since only the SSD itself is aware of how many blocks it has programmed. Intel wanted to represent its SSD lifespan as a function of the amount of data written per day, so Intel met with a number of OEMs and collectively they came up with a target figure: 20GB per day. OEMs wanted assurances that a user could write 20GB of data per day to these drives and still have them last, guaranteed, for five years. Intel had no problems with that.
Intel went one step further and delivered 5x what the OEMs requested. Thus Intel will guarantee that you can write 100GB of data to one of its MLC SSDs every day, for the next five years, and your data will remain intact. The drives only ship with a 3 year warranty but I suspect that there'd be some recourse if you could prove that Intel's 100GB/day promise was false.
Just like Intel's CPUs can run much higher than their rated clock speed, Intel's NAND should be able to last much longer than its rated lifespan
It's also possible for a flash cell to lose its charge over time (albeit a very long time). Intel adheres to the JEDEC spec on how long your data is supposed to last on its SSDs. The spec states that if you've only used 10% of the lifespan of your device (cycles or GB written), then your data needs to remain intact for 10 years. If you've used 100% of available cycles, then your data needs to remain intact for 1 year. Intel certifies its drives in accordance with the JEDEC specs from 0 - 70C; at optimal temperatures your data will last even longer (these SSDs should operate at below 40C in normal conditions).
Intel and Micron have four joint fabs manufactured under the IMFT partnership, and these are the fabs that produce the flash going into Intel's SSDs. The 50nm flash used in the launch drives are rated at 10,000 erase/programming but like many of Intel's products there's a lot of built in margin. Apparently it shouldn't be unexpected to see 2, 3 or 4x the rated lifespan out of these things, depending on temperature and usage model obviously.
Given the 100GB per day x 5 year lifespan of Intel's MLC SSDs, there's no cause for concern from a data reliability perspective for the desktop/notebook usage case. High load transactional database servers could easily outlast the lifespan of MLC flash and that's where SLC is really aimed at. These days the MLC vs. SLC debate is more about performance, but as you'll soon see - Intel has redefined what to expect from an MLC drive.
Other Wear and Tear
With no moving parts in a SSD, the types of failures are pretty unique. While erasing/programming blocks is the most likely cause of failure with NAND flash, a secondary cause of data corruption is something known as program disturb. When programming a cell there's a chance that you could corrupt the data in an adjacent cell. This is mostly a function of the quality of your flash, and obviously being an expert in semiconductor manufacturing the implication here is that Intel's flash is pretty decent quality.
Intel actually includes additional space on the drive, on the order of 7.5 - 8% more (6 - 6.4GB on an 80GB drive) specifically for reliability purposes. If you start running out of good blocks to write to (nearing the end of your drive's lifespan), the SSD will write to this additional space on the drive. One interesting sidenote, you can actually increase the amount of reserved space on your drive to increase its lifespan. First secure erase the drive and using the ATA SetMaxAddress command just shrink the user capacity, giving you more spare area.
96 Comments
View All Comments
aeternitas - Thursday, September 11, 2008 - link
Converting all your DVDs to divx is a silly idea. Why would you want to lose dynamic range and overall quality (no matter the settings) for a smaller movie size when 1TB costs 130$?SSD = Preformance (when done right)
HHD = Storage.
johncl - Tuesday, September 9, 2008 - link
Noise isnt a big problem on a 3.5" in a media pc as the other poster states. But heat can be a problem, especially if you plan on passively cool everything else in the computer. An SSD will solve both problems, but only if the SSD is the only disk in the system. From what I understand you want to have both in yours which makes sense since movies/music occupy a lot of space. In that case you will not experience any improved performance since the media would have to be read off the mechanical drive anyway.Your best bet would be to build yourself a small media server and put all noisy hot mechanical disks in that and use small SSDs on your media pc (and indeed any other pc). That way you get the best of both worlds, fast response on application startup/OS boot, silent and no heat - as well as a library of media. You would probably have to use a media frontend that caches information about all media on your server though so it doesnt have to wait on server harddisk spinup etc for every time you browse your media. Perhaps Vista Media Center already does this?
mindless1 - Thursday, September 11, 2008 - link
An SSD will not "solve" a heat problem. The hard drive adds only a small % of heat to a system and being lower heat density it has one of the less difficult requirements for cooling.Speed of the HTPC shouldn't be an issue, unlike a highly mixed use desktop scenario all one needs is to use stable apps without memory leaks then they can hibernate to get rid of the most significant boot-time waiting. Running the HTPC itself the OS performance difference would be trivial and the bitrate for the videos is easily exceeding by either storage type or an uncongested LAN.
piroroadkill - Tuesday, September 9, 2008 - link
To be honest most decent HDDs don't make significant noise anyway, even further quelled by grommets or suspending the drive.Also, the reads will occur on the drive you're reading the movie from - so if you plan to use an external HDD as the source, this will make no difference whatsoever.
dickeywang - Tuesday, September 9, 2008 - link
Imaging you have a 80GB SSD, with 75GB been already occupied by some existing data (OS, installed software, etc), so you only have 10GB space left, now lets say you write and then erase 100GB/day on this SSD, shouldn't the 100GB/day data all be written on the 5GB space? So each cell would be written 100GB/5GB=20cycle/day, so you will reach the 10000cycle/cell limit within less than 18months.Can someone tell me if the analysis above is correct? I guess when they say "100GB/day for 5 years", they should really take into account how much storage space that is un-occupied on the SSD, right?
johncl - Tuesday, September 9, 2008 - link
A good wear leveling algorithm can move about "static" blocks so that their cells are also available for wear. I do not know if the current implementations use this though. Anyone know this?Lux88 - Tuesday, September 9, 2008 - link
I remember reading a number of SSD reviews, but it's first time I read about the pauses. Indeed, quick search revealed 5 articles, starting from May 2007, but the conclusions only mentioned a high price and a small capacity as drawbacks. Nothing about freezing nor pauses. Some of these 5 probably were SCL-drives, some MLC.It's funny how a simple multitasking test can reveal an Achille's heel of large group of products, just when a product appears that doesn't suffer from this particular drawback.
Overall good article and good info. So good that all the previous articles on the matter of SSDs on this site seem bad in comparison. Thanks for the info anyway, better late than never ;).
eva2000 - Tuesday, September 9, 2008 - link
If the OCZ Core controller does indeed have 16KB on chip cache for read/writes maybe that's the problem as OCZ Core pdf states for their SSD"each page contains 4 Kbytes of data, however, because of the parallelism at the back end of the controller, every access includes simultaneous opening of 16 pages for a total accessible data contingent of 64 Kbytes"
????
araczynski - Tuesday, September 9, 2008 - link
looks quite promising. maybe within about 2 years they'll get the bugs worked out, a more realistic price, and an extended life span, and i'll replace my regular drives.yyrkoon - Tuesday, September 9, 2008 - link
"No one really paid much attention to Intel getting into the SSD (Solid State Disk) business. We all heard the announcements, we heard the claims of amazing performance, but I didn't really believe it. After all, it was just a matter of hooking up a bunch of flash chips to a controller and putting them in a drive enclosure, right? "You mean you did not pay attention? I know I did, because Intel has always been serious with things of this nature. That and they are partnered with Crucial(Micron) right ?. . . Now if this was some attempt at sarcasm, or a joke . . .
Seriously, and I mean VERY seriously, I was excited when Anandtech 'reported' that Intel/Micron were going to get into the SSD market. After all affordable SSDs are very desirable, never mind affordable/very good performing SSDs. That, and I knew if Intel got into the market, that we would not have these half-fast implementations that we're seeing now from these so called 'SSD manufactures'. Well, even Intel is not impervious to screw ups, but they usually learn by their mistakes quickly, and correct them. Micron (most notably Crucial) from my experience does not like to be anything but the best in what they do, so to me this seemed like a perfect team, in a perfect market. Does this mean I think Micron is the best ? Not necessarily. Lets me just say that after years of dealing with Crucial, I have a very high opinion of Crucial/Micron.
"What can we conclude here? SSDs can be good for gaming, but they aren't guaranteed to offer more performance than a good HDD; and Intel's X25-M continues to dominate the charts."
Are we reading the same charts ? These words coming from the mouth of someone who sometimes mentions even the most minuscule performance difference as being a 'clear winner' ? Regardless, I think it *is* clear to anyone willing to pay attention to the charts that the Intel SSD "dominates". Now whether the cost of admission is worth this performance gain is another story altogether. I was slightly surprised to see a performance gain in FPS just by changing HDDS, and to be honest I will remain skeptical. I suppose that some data that *could* effect FPS performance could be pulled down while the main game loop is running.
Either way, this is a good article, and there was more than enough information here for me(a technology junky). Now lets hope that Intel lowers the cost of these drives to a more reasonable price(sooner rather than later). The current price arrangement kind of reminds me of CD burner prices years ago.