Random Read/Write Speed

The four corners of SSD performance are as follows: random read, random write, sequential read and sequential write speed. Random accesses are generally small in size, while sequential accesses tend to be larger and thus we have the four Iometer tests we use in all of our reviews.

Our first test writes 4KB in a completely random pattern over an 8GB space of the drive to simulate the sort of random access that you'd see on an OS drive (even this is more stressful than a normal desktop user would see). I perform three concurrent IOs and run the test for 3 minutes. The results reported are in average MB/s over the entire time. We use both standard pseudo randomly generated data for each write as well as fully random data to show you both the maximum and minimum performance offered by SandForce based drives in these tests. The average performance of SF drives will likely be somewhere in between the two values for each drive you see in the graphs. For an understanding of why this matters, read our original SandForce article.

Desktop Iometer - 4KB Random Write (4K Aligned) - 8GB LBA Space

The numbers here are what you'll see echoed throughout the entire review. The 120GB Wildfire and Vertex 3 MAX IOPS perform like a 240GB Vertex 3. The Patriot and OCZ drives perform identically as they are similarly equipped.

Many of you have asked for random write performance at higher queue depths. What I have below is our 4KB random write test performed at a queue depth of 32 instead of 3. While the vast majority of desktop usage models experience queue depths of 0 - 5, higher depths are possible in heavy I/O (and multi-user) workloads:

Desktop Iometer - 4KB Random Write (8GB LBA Space QD=32)

Desktop Iometer - 4KB Random Read (4K Aligned)

Sequential Read/Write Speed

To measure sequential performance I ran a 1 minute long 128KB sequential test over the entire span of the drive at a queue depth of 1. The results reported are in average MB/s over the entire test length. These results are going to be the best indicator of large file copy performance.

Desktop Iometer - 128KB Sequential Read (4K Aligned)

Desktop Iometer - 128KB Sequential Write (4K Aligned)

A Note on Real World Performance AnandTech Storage Bench 2011
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  • GullLars - Thursday, June 23, 2011 - link

    I noticed the clear winner at your 4KB random read (QD3) test has been cleared from the chart. The C300 pushes over 90MB/s while the second highest, and the highest in this cart, is Vertex 3 240GB with 68MB/s. I feel this is worth noting, as the SF-2281 drives generally win with a good margin in many tests, but loose to a more than year old drive in small random reads at low queue depths.
  • Bannon - Thursday, June 23, 2011 - link

    Thanks for another good review Anand. I've been following the discussions in the Corsair and OCZ forums and while I'm interested in the super-fast speeds of the new SandForce drives I'm leery because of the problems a percentage of their customers are having. So, I was considering a 256GB Crucial M4 drive which seemed to do well in your review but was surprised when you recommended the Intel 510 drive as an alternative. Do you have concerns with the M4?
  • ocz2004 - Thursday, June 23, 2011 - link

    Hello everyone, as my first post in this thread let me identify myself as an OCZ employee. I’d like to thank everyone for their comments. Positive or negative, we appreciate all the feedback and take it very seriously throughout the organization. We continue to see a very small percentage of users with the BSOD issue but have made addressing this a high priority, and encourage any customers that have this or any issues to contact our customer service team. We have and will continue to work closely with SandForce and our platform partners for a final fix, and have spearheaded this effort among all manufacturers that utilize a SF solution. As mentioned in our previous public statement, we are also working on optimizations to the base code to minimize any performance delta associated with the temporary workaround. Thank everyone again for your support and feedback, and we will continue to work diligently on providing both premium performing and reliable SSDs to all our valued customers. We are willing to go above and beyond to make our customers happy; for anyone that is having this issue please contact support at drego @ ocz dot com
  • tecsi - Thursday, June 23, 2011 - link

    From Anand's comments:
    "It turns out that although the move from a hard drive to a decent SSD is tremendous, finding differences between individual SSDs is harder to quantify in a single real world metric...The best values in SSDs are going to be last year's models without a doubt."

    It appears that the best desktop SSD value--by far--is grabbing a 64GB SATA II boot/app drive (paired with a big HD), which are often rebated to ~$70. Although SATA III and 120GB/240GB look great on a specialized SSD racetrack, in the real world the performance difference appears to be a 5-10%, while paying just 30% of the $250 cost for a SATA III 120GB drive.

    Does this make sense or am I missing something? I was getting quite excited about SATA III and all the fawning over the Vertex 3, but this enthusiasm seems misplaced.
  • Impulses - Thursday, June 23, 2011 - link

    Only issue with that is that after formatting and installing the OS, a 64GB SSD doesn't leave you a lot of extra space... Depending on your needs that may or may not be an issue. I got an 80GB Intel X25-M for my desktop last year and it's a little tight, I have the luxury of having enough space for a couple of games but I do rotate which ones I have on it... I'm looking at 120GB drives but I'm waiting for prices to come down a little.

    I got a 40GB X25-V for my netbook tho and it's just for that kinda system... Win7 and the basic kind of programs that I use on my netbook all fit fine within <25GB, and with only 1.5GB of RAM the size of the hibernate file isn't a big concern. Still got enough space for a couple of movies when I travel.
  • FunBunny2 - Thursday, June 23, 2011 - link

    Over on Postgresql-performance, for one, there is not much love for anything less than full blown cap-backed SSDs, and even then, when used for database logs (not necessarily a good use of an SSD) 18 months is about the lifetime.

    So, using highly normalized (BCNF, which you shouldn't have to look up) X00 gig databases only on SSD (no HDD for logs and such) is a real torture test. Random access in a real world application. Oracle and MS have them. TPC, of course, has a bunch.
  • jdmstl - Thursday, June 23, 2011 - link

    I had a problem with the Vertex 3 240GB in a new Thinkpad W520. The bluescreen occurred at relatively light or idle usage, but seemed to have nothing to do with power save features. I tried disabling all such features in the bios, as well as a number of logical software fixes to no avail.
    Finally, I simply returned the drive to Microcenter for a refund rather than deal with the issues. I never posted my problems to OCZ, although I read the related forum posts for clues.
    I suspect that many people did the same, so I would not trust any defect rate figures based on number of forum posts. It would be more accurate to check the return rate, but I suspect that many people just ignore the BSODs and live with it without reporting any issue, assuming it will all work out eventually.
    OCZ tries to deny or downplay issues without taking full responsibility. They did the same thing with JMicron controller problems a few years ago. (Not that any other brands were more honest or forthcoming.)
    I think I will stick with Intel from now on, although I had good luck with 4 of the original Vertex Indilinx drives that are still running fine in my home desktop PCs.
  • jwilliams4200 - Friday, June 24, 2011 - link

    OCZ is definitely the leader when it comes to their propaganda machine. It seems even Anand has gotten brainwashed by it.
  • Concillian - Friday, June 24, 2011 - link

    It really helps to read that page to put the performance picture in perspective. This kind of thing is difficult to get a feel for when looking at reviews.

    It's easy to tell which is faster from benchmarks, but it's not always easy to tell how much that speed will translate into actual perceivable improvement for daily workloads.

    I think you should throw in a few "vs. rotating storage" charts in every SSD review just to help demonstrate the performance differences to those contemplating the jump to SSD. Many of your readers have made the jump and are looking at SSDs vs. SSDs, but I'll bet a fair amount are still looking at the value vs. a hard drive and haven't necessarily seen the history of all the articles that show these differences.
  • cactusdog - Friday, June 24, 2011 - link

    I respect Anands opinions but the timing of his reviews and comments(regarding OCZ) makes it seem he is working with OCZ. Like he wont say anything negative unless OCZ have already addressed it.

    Its strange this review hit just after the new firmware 2.09 was released. The 2.09 firmware that is supposed to fix any BSOD issues.

    Going back over previous reviews, Anand never mentioned any of the user complaints about slower 25nm nand (and the use of slower hynix or second rate Spectek nand) until AFTER OCZ had put out an official statement about it. Until OCZ had promised to swap drives and promised not to use dodgy nand again.

    The point is Anand seems to have a direct line to OCZ and he will not address users concerns until AFTER OCZ has officially recognised it in some way.

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