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.

Iometer - 4KB Random Write, 8GB LBA Space, QD=3

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:

Iometer - 4KB Random Write, 8GB LBA Space, QD=32

Iometer - 4KB Random Read, QD=3


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.

Iometer - 128KB Sequential Write

Iometer - 128KB Sequential Read

The Secret to Interleaving AnandTech Storage Bench 2011
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  • B0GiE - Friday, May 6, 2011 - link

    NIce to see the review, shame you never looked at the Vertex 3 Max IOPS versions though. Any chance you can get hold of them and report on the differences?
  • Anand Lal Shimpi - Friday, May 6, 2011 - link

    Still waiting on my review sample, I'm guessing it'll be next week :)

    Take care,
  • sequoia464 - Monday, May 9, 2011 - link

    Any Idea when the Samsung 470 review will be up?? Quite interested in your take on this drive.
  • cearny - Friday, May 6, 2011 - link

    Realyy great review, but in my case it raises even more doubt. I was about to pull the trigger on the 120GB version of the Intel 510, but now I don't know what performance to expect at all.

    Do you think you'll also be able review the lower-capacity Intel 510/320 drives in the near future?
  • Anand Lal Shimpi - Friday, May 6, 2011 - link

    The 120GB 510 is next on my list :)

    Take care,
  • cearny - Saturday, May 7, 2011 - link

    That's great news! Looking forward to the review :D
  • M@rc - Friday, May 6, 2011 - link

    I have a question regarding TRIM: if I install both Windows 7 (TRIM support) and OS X (no TRIM) on the same SSD, will that potentially cause problems?
  • HilbertSpace - Friday, May 6, 2011 - link

    Good question, I'm guessing it would only run TRIM on the windows partition and not the Mac one.
  • ajp_anton - Friday, May 6, 2011 - link

    I don't need more than 120GB. Any chance of a review of Intel's 120GB version?
  • jjj - Friday, May 6, 2011 - link

    Any word on a new firmware rls date? see http://www.xtremesystems.org/forums/showpost.php?p...

    Anyway waiting eagerly for M4 and Max IOPS @ 120GB reviews since those 2 seem to be the most interesting given the price/perf ratio.

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