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Four SSDs Compared — OCZ, Super Talent, Mtron
MojoKid writes "Solid State Drive technology is set to turn the storage industry on its ear — eventually. It's just a matter of time. When you consider the intrinsic benefits of anything built on solid-state technology versus anything mechanical, it doesn't take a degree in physics to understand the obvious advantages. However, as with any new technology, things take time to mature and the current batch of SSDs on the market do have some caveats and shortcomings, especially when it comes to write performance. This full performance review and showcase of four different Solid State Disks, two MLC-based and two SLC-based, gives a good perspective of where SSDs currently are strong and where they're not. OCZ, Mtron and Super Talent drives are tested here but Intel's much anticipated offering hasn't arrived to market just yet."
One manufacturer makes both an SLC and MLC drive. RTFM.
They tested two (2) different OCZ SSD models, one with SLC NAND Flash memory chips, and the other with MLC NAND Flash memory chips. 2+1+1=4
I know, I RTA...
You know, we keep talking about solid state as its better because there are no moving parts, and less wear, but chips and circuits have plenty of moving electrons and go through a lot of thermal stress. I know that for a lot of applications a circuit can seem to be more reliable, but do we really have a sufficient experience to make such a sweeping statement that in fact solid state is more -reliable- than a mechanical system? There are some steam trains out there that are running and are over 100 years old... do we really think that a CPU or a RAM or a motherboard can live that long?
This is my sig.
Yet another SSD review by clueless PC dweebs.
The whole point of SSDs is that they have no moving parts, so they don't have the seek time and rotational latency of spinning disks. That translates into faster random access. As the review says:
So what do they measure? Sequential transfer rates.
Gah.
I had a 286 laptop with MS-DOS in ROM.
Someone wake me up when there's a 1TB SSD for $250 that can do unlimited rewrite ops.
Um, even mechanical hard drives cannot promise unlimited rewrite ops. Maybe you want lower your sights jut a tad?
Bearded Dragon
http://www.hothardware.com/printarticle.aspx?articleid=1211
RTFM? Shit... comments, articles, now I have to read a damn manual too. Jesus Slashdot is getting harder and harder these days.
Sorry, teleporters just kill you and then make a copy. A perfect, soul-less copy.
For instance, MLC NAND memory has between 1,000 and 10,000 write cycles per cell, SLC memory about 100,000. Some applications will be more write intensive, so they'll wear out the memory faster.
That's why modern CF, SD, and SSD controllers spread writes to a single logical sector over multiple physical sectors. They also dedicate 5 to 7 percent of their space to spare sectors in case one wears out; this accounts for the difference between a GB and a GiB. For example, a half-full 16 GB SSD with blocks of 128 KiB has over 60,000 free blocks. If your app makes 864,000 writes per day (10 writes per second 24/7), then the wear leveling circuitry would go through the entire free memory just under 15 times a day. If your SLC is guaranteed for 100,000 erases per block, then it should still last over 18 years.
My point being, they spent so much time measuring performance with sequential data transfer and write speed, when at least in the short term (next 5-10 years) these are pretty much just going to be OS drives where those benchmarks are inconsequential. Let's test system performance in the setup I mentioned. Test Autocad performance with the app on the SSD. Test Crysis performance with the game data on the SSD. Run PCmark or similar benchmark utility installed on the SSD and compare it to the typical 7200rpm or 10,000rpm hard drive that is in a typical desktop today. Then we'll have a useful benchmark and a really good basis to determine whether or not we're getting close to price vs. performance feasibility.
I am not an expert by any stretch but it seems to me that write speed issues, at least when it comes to relatively small amounts of writing, could easily be mitigated with a very long on-board RAM buffer controlled by the drive... and by very large, I mean like 1GB at least. And to keep it stable, a capacitor should be enough to keep it alive when power drops to commit any changes in buffer to the SSD storage. Maybe what I speak of is impossible or ridiculously expensive, but I don't think either is the case.
You can set up your machine this way right now if you want. Just put /home on a traditional disk and have the kernel and maybe a couple more trees of system files on an SSD. This way your SSD doesn't wear out as fast and you have super-quick read access to the kernel and settings.
If you're running something other than linux I'm sure there's a less transparent way of doing this. Mac OS doesn't really let you set mountpoints with Disk Utility but it won't freak out if you put in your own (MacFUSE does this). You may have to do so in a script though since Mac OS ignores the contents of /etc/fstab I thought. Someone out there probably knows for sure.
Someone wake me up when there's a 1TB SSD for $250 that can do unlimited rewrite ops.
Let me guess, you want a car's drivetrain to promise "unlimited mileage" and your homes A/C refrigerant to promise "unlimited compression/decompression cycles".
I hate to be the one to break it to you, but words like "unlimited" are marketing words only. EVERYTHING is limited and finite. In this case, consumer protection laws state that 7 years of normal usage is long enough to be considered "lifetime" or "infinite" or "unlimited" and all sorts of other key words and tricky phrases.
Those mechanical drives you are comparing SSDs to? They don't offer "unlimited rewrites" except in the marketing sense. 7 years of normal usage. In that same sense, SSDs are already offering unlimited rewrites as they have enough rewrite cycles to last 7 years of normal usage. Just like the mechanical drives.
Modding Trolls +1 inciteful since 1999
Lots. For a high-speed SLC (i.e. something that will equal a cheap 7200rpm spinning platter), you'll pay $400+ for a 64gb and $700+ for a 128gb at this point. Basically, they're completely economically infeasible at anything larger than the 4/8gb you see being used to store the OS and apps in netbooks, unless you have a critical need to access a lot of data at high speed while driving a truck over a small post-apocalyptic wasteland.
By what WITCHCRAFT would thou know the article contents?
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Man, I just realized how old I'm getting ...
No you didn't. You realized that awhile back but forgot.
Someone wake me up when there's a 1TB SSD for $250 that can do unlimited rewrite ops.
Ah, finally! We've waited for you to go away forever, and here you offer it to us on a silver platter!
SSD's will reach $/GB equity for enterprise disks within 2 years. They already beat them on $/IOPS, and will soon on $/MB/s.
A reasonable projection for SATA is 6-7 years. However, if you know technology, that's like talking about what's going to happen in a thousand years. One just cannot know. The cross-industry pressure is definitely going to incentivize the spinning media makers to work on areal density.
In spite of that, I feel pretty sure that SSD's are going to wipe out Tier 1 entirely. Tier 1 is an IOPS-centric thing. The real formula is something like $/IOPS/GB or some weighted mutation. When that hits, 15K drives are DEAD.
And I doubt very much you will EVER see a 20K drive. Power is something like the cube of the RPM. Such a drive would be dead on arrival.
C//
These guys are idiots. A few points:
- They 'cheated' on ATTO, only configuring it to start at 8k. Last I checked, default sector size is 512b. Regular day-to-day apps, such as Outlook, perform random sector-level access to the PST when downloading mail.
- If you're going to do an SSD roundup, how about at lest grabbing a few drives off of the SSD top 10. Specifically, Memoright (#1 on that list) makes an SLC drive that competes with the other SLC drives on price, yet outperforms them all: http://www.storagesearch.com/ssd-top10.html
- Disclaimer: I own a Memoright drive. I don't claim to be a fanboy, I just did my research beforehand (along with trying out a few other drives), and found the best thing going at the time.
- The Intel drives, expected to come out this month, are likely to bury everything on that review.
this sig was brought to you by the letter
I got a Core 64GB. I build large java projects. This is for my workstation, not a laptop. Power and quiet were not the reasons for my experimental purchase.
I aimed to slash my build time for complex scenarios.
I thought the Compile -> Jar -> War -> Deploy -> Expand -> Launch would be greatly spead up as the files would be accessed quickly.
I hoped effectively for a much more targeted and capacious file cache/ RAM disk.
Unfortunately, the hype does not turn out to be true.
The enormous time cost of writing files smaller than 8MB (!) [see footnotes] completely counters any read speed increase. Building a proect is making thousands of 2KiB files : one of the most pathological cases for these drives.
So is it slow? No, it's just as quick as a sluggish 7K250, but then again I just coughed up £179 for the privelege of the same speed.
So I'm ebaying mine to someone who wants it for a light and quiet laptop, perfect.
-----------------
Some "Terrible small write performance" links I found during research:
* http://www.xbitlabs.com/articles/storage/display/ssd-iram_6.html
* http://www.alternativerecursion.info/?p=106
[% slash_sig_val.text %]
It's an SSD, there is no platter!
It doesn't mean much now, it's built for the future.
Speaking of handicaps and stalls, isn't that exactly what's going to happen to many of these 1st- and 2nd-generation SSD drives when they reach their maximum # of write cycles and suddenly fail to be writable anymore?
Just like SATA and SCSI drives, it will just build up bad sectors as the system tries to write information, resulting in a "shrinking" drive.
It is actually much less likely this type of storage device will have a sudden, catastrophic failure, when it only takes one moving part to foul in a mechanical drive to destroy everything it contained.
I don't find a benefit or obvious advantage in a device that requires wear-leveling to keep from wearing itself out. The fact that it degrades its storage capacity gracefully instead of all at once doesn't offset that swap files can really work over mass storage devices and the first bad sectors have been known to start showing up after only weeks of use in some cases.
Magnetic media does this too, just not as intelligently. Magnetic media waits until a sector is nearing failure, then reads the data (hopefully) and moves it to a new sector.
You can query your magnetic drive to get a list of bad sectors. The list grows over time.
I set my Asus EEE up this way. The SSD has the OS on it, only. I added in an SD card to hold the temp, var, swap, and home directories. While it's not super speedy, it saves the SSD from major use. And should I ever need to boot it under duress at the border, given a few seconds warning, the camera won't have any pictures on its SD card, and the laptop won't boot due to the pictures on its card.
Velociraptor = Distiraptor / Timeraptor
What I don't understand is why the big whoop over SSD. Sure in special cases like music players and laptops,stuff that gets slung around,yeah i can see it. But why would you want one in any other place? hell,I got rid of some 400Mb(yes with an Mb. We thought they were big back in the day) drives that still purred like kittens. I think in all my years of abusing my HDDs with video transcoding and editing I have killed a grand total of two,and one of those i was able to get back with the bosses copy of spinrite.
So I just don't get why everyone is getting so buzzed about an SSD with this "countdown to extinction" hanging over its head when the HDDs just last so much longer. And with a $15 USB adapter I can take my old drives as I trade up and use them for easy backups and portable storage. So while I might get one for my laptop(when they are cheap enough) and have flash in my media player and camera I just can't see myself wanting it to many other places,and certainly not replacing my reliable HDDs. But as always this is my 02c,YMMV
ACs don't waste your time replying, your posts are never seen by me.
The big win with SSDs is low latency read access - you don't have to wait for rotation or seek time to start fetching your data. That's really useful for many kinds of data applications, speeding up transactions in databases, etc. If you RTFA, and look at some of the benchmarks like Windows Startup, they totally smoke rotating disks - and if you're trying to run servers in a datacenter, you've got less downtime if you ever have to reboot the things.
They also consume less power, which is good for some kinds of applications, though they cost enough you're not going to save any money.
Battery-backed-RAM-based SSDs are a different game entirely, because they also give you very fast write speed, and that's where a lot of the whoop comes from; according to this article, the SSDs were a bit slower than a 10Krpm disk drive, so that doesn't apply here. The RAM type are really useful for database commits, where you need to get the journal saved to stable storage so you can go on to the next transaction. But even there, the low read latency of the flash-based disks is going to help a lot, especially for multi-user applications.
There's also the perception of reliability - I've certainly had lots of disk drive failures on mechanical disks.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks