Random Read/Write Speed

This test writes 4KB in a completely random pattern over an 8GB space of the drive to simulate the sort of random writes 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.

I've had to run this test two different ways thanks to the way the newer controllers handle write alignment. Without a manually aligned partition, Windows XP executes writes on sector aligned boundaries while most modern OSes write with 4K alignment. Some controllers take this into account when mapping LBAs to page addresses, which generates additional overhead but makes for relatively similar performance regardless of OS/partition alignment. Other controllers skip the management overhead and just perform worse under Windows XP without partition alignment as file system writes are not automatically aligned with the SSD's internal pages.

First up is my traditional 4KB random write test, each write here is aligned to 512-byte sectors, similar to how Windows XP might write data to a drive:

4KB Random Write - MB/s

Unaligned 4KB random writes are a bit lower, but nothing tremendous. For some reason both of the OWC Mercury drives actually performed lower than our Vertex LE sample in this test. These should all be the same drive. As we saw in the last review however, in order to better represent performance under modern OSes we need to look at 4K aligned writes since that's what ends up happening most of the time.

4K Aligned - 4KB Random Write - MB/s

Peak random write performance isn't nearly as good on the 50GB drive. While the 100GB SF-1500 based drives can muster around 160MB/s, the 50GB drive can only manage 44.2MB/s. It's not a deal breaker by any means, and shouldn't really be noticeable in real world usage - but this is the downside to the 50GB drive. Note that at 44.2MB/s, it's still roughly the same speed as Intel's X25-M G2.

4KB Random Read - MB/s

Sequential Read/Write Speed Overall System Performance using PCMark Vantage


View All Comments

  • ayembee - Tuesday, March 9, 2010 - link

    ...given my 200GB Vertex 2 LE lasted 6 days :

    however, based on the OCZ support forums it could be the OCZ firmware rather than a specific hardware issue, as it seems they they are getting very similar-sounding bricks on several kinds of vertex models.
  • Hrel - Sunday, March 7, 2010 - link

    Now I only need to wait for SSD's in this price range to drop under $1 per GB; and let me add that after getting used to 12cents per GB I think I'm being extremely generous! Reply
  • OWC Grant - Monday, March 1, 2010 - link

    As far as reselling review units, most manufacturers DO sell their review units and other products clearly marked as "open box", B stock, or refurbished and thus provide users with another purchase option. We offer these types of products in our monthly "clearance/garage sale" promo and are very well liked by our newsletter readers as great "insider" deals.

    Our statement of all the drive sizes (50/100/200GB) offering the same performance in terms of raw sustained data transfer rates was and is still true. As noted in Anand's final summary and direct communication with us, the overall performance of the 50GB model "looks quite good" and "performance is nearly identical in call cases except one." (a small random write file) We are looking into that one instance and will advise on any outcome.

    Thanks as always to Anand and you readers for your interest in SSD's in general and our offerings in that category.
  • jed22281 - Friday, March 26, 2010 - link

    "As noted in Anand's final summary and direct communication with us, the overall performance of the 50GB model "looks quite good" and "performance is nearly identical in call cases except one." (a small random write file) We are looking into that one instance and will advise on any outcome."

    So what was the outcome?

  • skimike - Monday, May 3, 2010 - link

    Out of curiosity, do you know if OWC has a secure/sanity erase utility for the OWC Mercury Extreme 100GB drive? I called OWC's tech support line and they didn't know anything about it. And the drive password used by hdparm in Linux isn't set to NULL so I can't use hdparm, either. Reply
  • monomer - Monday, March 1, 2010 - link

    Dailytech posted an article on Friday saying that JMicron will be releasing a new controller with a 128MB DRAM cache soon. Does anyone know if they actually fixed their random access problems, or did they just throw more cache at it to try to cover it up? Reply
  • tuskers - Monday, March 1, 2010 - link

    Something I'd love to see is how much software compile times improve with an SSD. As a professional software engineer, I'd love to see whether SSDs would improve a common real-world task like this. Reply
  • hyc - Monday, March 1, 2010 - link

    Yes, noticeably.

    I write code all day. All of my machines now have SSDs as their primary drive. 256GB G.Skill Titan in my desktop, 256GB Samsung in my current laptop, 128GB Transcend PATA in my old laptop, 120GB OCZ CoreV2 floating on an eSata adapter for quick bulk copies.
  • arklab - Monday, March 1, 2010 - link

    Pardon my ignorance, but I'm new to SSD's.
    I (think) I read in your first review that only Sand Force is able to make utilities for these (OWC and OCZ LE) drives.

    Does this include the trim command (for Windows 7 use), or can we just use some "generic" command?

    What would OSX users do?

  • fictionfree - Monday, March 1, 2010 - link

    I've purchased a couple items from OWC in the past - can't say I'm a fan of the company. It wouldn't surprise me if they resold review drives. I purchased an external Firewire drive from them a few years ago, and when the internal drive died, I took the case apart to see that it was a refurbished drive. I didn't buy a refurb drive, I bought a brand new drive - but they filled the case with a refurb. Not cool - and they refused to do anything to make it right.

    Just my 2 cents, but I find them to be shady.

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