Random Read/Write Speed

This test reads/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.

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

Random write performance is at the lower end of the Indilinx spectrum, but definitely competitive in that space. Obviously even as a slower SSD the SiliconEdge Blue is an order of magnitude faster than even the fastest desktop hard drives.

The chart below shows that the SiliconEdge Blue performs the same regardless of whether you align transfers to 4KB boundaries or not:

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

Random read performance is the only area where Western Digital's SSD actually noticeably falls behind the Indilinx drives:

4KB Random Read - MB/s

At 21.8MB/s it's much faster than a hard drive, but a good ~15MB/s slower than an Indilinx drive. It is in the same class of performance as the Toshiba based SSDNow V+ and the Samsung RBB based drives.

Sequential Read/Write Speed Overall System Performance using PCMark Vantage
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  • chuckbam - Saturday, March 20, 2010 - link

    I buy Intel for the Intel SSD Toolbox utility. With win7, I load the Intel chipset inf, Matrix Storage Manager and am not sure if Trim still works.

    I am happy to see WD into this market. Prices need to come WAY DOWN!
    Reply
  • Sabresiberian - Saturday, March 13, 2010 - link

    As a great fan of the Raptor series drives, what I want from WD is the same concept in SSD: the top performance and super reliability it is. The down side of course in a VelociRaptor is its relative price - and, as expensive as SSDs still are, a comparable price for an SSD "VelociRaptor" would be extreme.

    Still, it's what I want, and I could certainly see me building a high-end system using smaller capacity WD SSD "Raptors" in Raid 0 for that extreme performance goofy people like me want to have. If I get an extra few grand handed to me, I would use larger drives, of course.

    Anyhoo, this drive is not what I want to see from WD (unless of course it really does kick reliability butt over its competitors). Hopefully by the time I build another high-end rig (just built one so it will be awhile, likely) WD will have what I want (or someone), a SSD successor to VelociRaptor mechanical hard drives.
    Reply
  • liquoredonlife - Wednesday, March 10, 2010 - link

    Great article Anand! Also thanks for reiterating the incompatibility with gen2 unibody macbook pro's and particular SSDs. Will you be able to test this SSD with your mbp? Reply
  • heulenwolf - Wednesday, March 10, 2010 - link

    Anand mentioned some possible convergence between magnetic and solid state drive firmware development. Could this mean the mythical hybrid drive is down the road somewhere? With single spindles holding in excess of 300 GB and SSDs not even filling the 2.5" form factor, isn't there room for both? If not both storage types in one drive then maybe both storage types in one drive slot? Then you could have the boot drive be the super fast SSD and the advantage of cheaper, higher-capacity storage of a single-spindle magnetic drive in a single laptop. I think this dual-drive approach could be a better solution than the hybrid drive until caching in drive controllers becomes smarter. Reply
  • GullLars - Sunday, March 07, 2010 - link

    These drives clearly don't support NCQ, as IOPS don't scale with QD.
    The rating of 5000 IOPS is about the same as the rating of a single NAND TSOP. You can literaly get the same random IOPS performance from a thumbnail USB drive.
    Reply
  • ky - Thursday, March 04, 2010 - link

    Can someone explain why there's a dropoff in performance between the 100GB and 50GB Mercury Extreme SSDs in the 4K Aligned random write test? Reply
  • cactusdog - Thursday, March 04, 2010 - link

    Oh well nothing to see here either. I dont see how they can justify the price. A SSD with a PCB and some chips should be cheaper to make than a mechanical hard drive with moving metal parts. Fair enough to pay a little extra for new tech but this is ridiculous. Reply
  • Hrel - Wednesday, March 03, 2010 - link

    I'd really like to see performance of two 7200rpm drives in a striped RAID thrown into these charts. So please get on that. Reply
  • 7Enigma - Thursday, March 04, 2010 - link

    I'll save you the time of waiting.

    -Sequential Read and Write: Near twice the performance of a single drive

    -Random 4K read/write: Just as bad as a single drive

    Fin~
    Reply
  • GeorgeH - Wednesday, March 03, 2010 - link

    Going from WD's HDD naming conventions I would expect average but reliable performance from a "Blue" SSD, and that appears to be exactly what they've delivered, albeit at a ridiculously high price.

    The WD SSD I'm really interested in is the "SiliconEdge Black", a drive that will hopefully be forthcoming after their sales division puts down the crack pipe and gets serious about SSD pricing.
    Reply

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