The SSD Relapse: Understanding and Choosing the Best SSD
by Anand Lal Shimpi on August 30, 2009 12:00 AM EST- Posted in
- Storage
One Tough Act to Follow
What have I gotten myself into? The SSD Anthology I wrote back in March was read over 2 million times. Microsoft linked it, Wikipedia linked it, my esteemed colleagues in the press linked it, Linus freakin Torvalds linked it.
The Anthology took me six months to piece together; I wrote and re-wrote parts of that article more times than I'd care to admit. And today I'm charged with the task of producing its successor. I can't do it.
The article that started all of this was the Intel X25-M review. Intel gave me gold with that drive; the article wrote itself, the X25-M was awesome, everything else in the market was crap.
Intel's X25-M SSDs: The drives that started a revolution
The Anthology all began with a spark: the SSD performance degradation issue. It took a while to put together, but the concept and the article were handed to me on a silver platter: just use an SSD for a while and you’ll spot the issue. I just had to do the testing and writing.
OCZ's Vertex: The first Indilinx drive I reviewed, the drive that gave us hope there might be another.
But today, as I write this, the words just aren't coming to me. The material is all there, but it just seems so mature and at the same time, so clouded and so done. We've found the undiscovered country, we've left no stone unturned, everyone knows how these things work - now SSD reviews join the rest as a bunch of graphs and analysis, hopefully with witty commentary in between.
It's a daunting, no, deflating task to write what I view as the third part in this trilogy of articles. JMicron is all but gone from the market for now, Indilinx came and improved (a lot) and TRIM is nearly upon us. Plus, we all know how trilogies turn out. Here's hoping that this one doesn't have Ewoks in it.
What Goes Around, Comes Around
No we're not going back to the stuttering crap that shipped for months before Intel released their X25-M last year, but we are going back in the way we have to look at SSD performance.
In my X25-M review the focus was on why the mainstream drives at the time stuttered and why the X25-M didn't. Performance degradation over time didn't matter because all of the SSDs on the market were slow out of the box; and as I later showed, the pre-Intel MLC SSDs didn’t perform worse over time, they sucked all of the time.
Samsung and Indilinx emerged with high performance, non-stuttering alternatives, and then we once again had to thin the herd. Simply not stuttering wasn't enough, a good SSD had to maintain a reasonable amount of performance over the life of the drive.
The falling performance was actually a side effect of the way NAND flash works. You write in pages (4KB) but you can only erase in blocks (128 pages or 512KB); thus SSDs don't erase data when you delete it, only when they run out of space to write internally. When that time comes, you run into a nasty situation called the read-modify-write. Here, even to just write 4KB, the controller must read an entire block (512KB), update the single page, and write the entire block back out. Instead of writing 4KB, the controller has to actually write 512KB - a much slower operation.
I simulated this worst case scenario performance by writing to every single page on the SSDs I tested before running any tests. The performance degradation ranged from negligible to significant:
| PCMark Vantage HDD Score | New | "Used" |
| Corsair P256 (Samsung MLC) | 26607 | 18786 |
| OCZ Vertex Turbo (Indilinx MLC) | 26157 | 25035 |
So that's how I approached today's article. Filling the latest generations of Indilinx, Intel and Samsung drives before testing them. But, my friends, things have changed.
The table below shows the performance of the same drives showcased above, but after running the TRIM instruction (or a close equivalent) against their contents:
| PCMark Vantage HDD Score | New | "Used" | After TRIM/Idle GC | % of New Perf |
| Corsair P256 (Samsung MLC) | 26607 | 18786 | 24317 | 91% |
| OCZ Vertex Turbo (Indilinx MLC) | 26157 | 25035 | 26038 | 99.5% |
Oh boy. I need a new way to test.
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jtleon - Tuesday, September 8, 2009 - link
Yes I fell asleep atleast 3 times reading this article (it IS Monday afterall)Yes, Indilinx clearly rocks the SSD world - Now I know thanks to Anand!
Stories like this set the standard for all review sites - I don't come away with the feeling I was just sold a bill of goods by some schiester in Intel's pocket, or otherwise.
Great Job Anand! Keep them coming!
SSDdaydreamer - Tuesday, September 8, 2009 - link
I too am wondering whether TRIM will be available on the Intel Drives for Windows XP or Vista. I seriously doubt it, as the OCZ Wiper Tool appears to only be available for Indilinx controllers. Perhaps Intel will introduce their own wiper utility. I am leaning towards the OCZ Vertex or Patriot Torqx drives, as I am quite content with Windows XP and Windows Vista.I have an itchy trigger finger on these SSDs, but I want to hold back for the following unknowns.
1. I would like to use the NTFS file system for my drive, but I am unsure of the proper/ideal block size.
2. I would merely like to image my existing Windows Installation, but I am worried that performance or stability problems will arise from the NTFS file system. A fresh install could be in order, but it is preferred to image.
3. Is there a way to change the size of the spare area? Maybe I have the wrong idea (perhaps only format part of the drive, unformatted space goes appends to the spare area?) I am willing to sacrifice some of the usable partition space for an increased spare area for improved performance.
4. Are there complications with multiple partitions? If there are multiple partitions on the drive (for multi-boot) do they all share the same spare area? Is it possible to allow their own respective spare areas?
Is there anybody out there that could enlighten me? I'm sure others would do well to have the answers as well. If I make any discoveries, I will be sure to post them.
Thanks in advance.
bradhs - Monday, September 7, 2009 - link
IS there a "Wiper" app for Intel X-25m G2 drives? For people who don't have Windows 7 (TRIM) and want to keep the Intel X-25m G2 running smooth.smjohns - Tuesday, September 8, 2009 - link
No there is no wiper tool for Intel drives at the mo. In addition to this the current firmware on the Intel drives do not have TRIM enabled. I guess this will be released soon after Windows7 is released. I think I have read somewhere that Intel are working on a TRIM version of it's Matrix Storage Manager software that will provide this functionality to the other operating systems.Burny - Monday, September 7, 2009 - link
As many before me: great article! I learned a lot about SSD's. Even up to the point i'm ready to buy one.I still have 2 questions tough:
2. Will TRIM be available on the G2 Intel drives for sure? Some sources doubt this: http://www.microsoft.com/communities/newsgroups/en...">http://www.microsoft.com/communities/ne...t=&l...
3. As I understand, TRIM will work on a firmware level. That implies that TRIM will also function under Windows XP or any OS for that matter? Then why the need to build another TRIM into Windows 7? Or does a TRIM firmware enabled SSD simply allows the OS to use TRIM?
Thanks!
smegforbrain - Monday, September 7, 2009 - link
While I consider myself handy with computers, I'm not the best technical mind when it comes to the details. You do an excellent job of presenting everything in a manner that it can be understood with little difficulty. I look forward to future articles about SSDs.I do have a question I'm hoping somebody can answer. I'm as interested in the long-term storage outlook of SSD drives as I am every day use. I've seen it said that an SSD drive should hold its charge for 10 years if not used, and it was discussed a bit earlier in this thread.
Yet, none of my current mechanical hard drives are more than 3 years old; none of my burned DVDs/CDs are older than 5 years. It seems far more likely that I would replace an SSD for one with a greater storage capacity after 5 years tops than to expect one to be in use, even as archival storage, for as long as 10 years.
So, is the 10 year 'lifespan' even going to be an issue with archival storage for most people?
Will this worry over the life span of an SSD become even less of an issue as the technology matures over the next couple of years?
Starcub - Tuesday, September 8, 2009 - link
"So, is the 10 year 'lifespan' even going to be an issue with archival storage for most people?"No, but who takes wads of money out of their wallet to store it on their shelf?
smegforbrain - Tuesday, September 8, 2009 - link
"No, but who takes wads of money out of their wallet to store it on their shelf?"That is simply assuming that they will remain as expensive as they are now. They won't.
BlackSphinx - Sunday, September 6, 2009 - link
Hello! I'm taking the time to comment on this article, because I am very thankful for all of these awesome write-ups on SSD.I'm in the process of building an heavily overclocked i7 rig for gaming and video edition, and I was going to jam 2 Velociraptors in Raid0 in there. Why? I had only heard bad things about SSDs in the past.
Reading your aticles, who are, while in depth, very clear and easy to understand, I understand much better what happened in early SSDs, what's so good about recent Indilinx and Intel SSD, and, truly, why I should forgo mechanical drives and instead go the SSD route (which, frankly, isn't more costly than a Raid0 raptor setup). In short, these articles are a great service to the end users just like myself, and if they were intended as such, you have passed with flying colors. Congratulations and thanks.
Transisto - Sunday, September 6, 2009 - link
Could someone reset my brain as to why there is no way to get a (very noticeable) improvement from USB thumb-drives. I mean these thing also get 0.1 ms latency.It's a bit extreme but for the same price I could get 9 cheap 8gb SLC usb drive for around 20$ each and put them in three separate PCI-USB add-on card (5$)
They would saturate the USB controler with 3 drive in it so I Could get around 140mb/s read and 60mb/s write.
Say you manage to merge that into a raid or ... ? Is eboost or Readyboost any good at scaling up ?