There are plenty of benchmarking tools available but storage professionals mostly use IOmeter. Unfortunately IOmeter is a little tricky to use. You really need to read the user manual first. I have frequently seen users trying to run IOmeter tests without success. Being human, most of us hate to read the manual and with IOmeter this can lead to problems. I hope this short post will help you to get the wanted results. First off, you need to know that IOmeter recognizes 2 different volume types:

• un-partitioned disks (blue icon disk), or
• formatted disks (yellow icon with a red slash though it)

With un-partitioned disks you can start the test at once, but to run with formatted disks you need a test file. The test file must be placed in the root directory and named: iobw.tst. By default IOmeter will create the test file if not found. The problem is that nowadays volumes are very big, and IOmeter runs very slowly. It’s much faster to create the test file using the TestFileCreator.exe from Open-E. Please run it in order to create iobw.tst with any size you desire. You can run: TestFileCreator.exe 100G in order to create a file of exactly 100GB.

To find out your storage performance there are a few typical test configurations you may want to run. Here are some example results of a FC Volume created on DSS V6 with FC HBA dual 4Gb and MPIO.

So, if your goal is to obtain the maximum MB/sec please create a test set up with 2-4 workers, using a block size of 256k and 100% sequential read or write. In our case the sequential read shows the best result: 772 MB/sec! Please make your settings very carefully and make sure all workers use the same test configuration! If you forget to add your [256kB, 100% sequential read] configuration to every worker you will be surprised with very low results because the default test settings use 2kB block and mixed random/sequential and read/write pattern. So instead of the desired 772MB/sec you might see 100 times less, i.e. ~ 7MB/sec.

Download DSS V7

Janusz Bak

Chief Technology Officer

Janusz Bak joined Open-E in 1999 and has been serving as Open-E's CTO ever since. Janusz has over 30 years of software engineering experience and is a recognized expert on storage technologies. Before Open-E, Janusz headed up German support operations at Aztech Systems and at Mega.

20 Comments

  • Yin /

    20, 07 2015 06:34:19

    hi,
    need some help please .
    i need to test 50Gb Big files * 4 copies in parallel repeating (copy, delete, copy) for 1/2 hour.
    Can any one tell me how to configure ?
    Thanks

    Reply

    • karolina.pletnia /

      22, 07 2015 10:22:42

      Dear Yin,

      Unfortunately we are not able to help you by answering your comment. Please create a ticket with our Technical Support team. They will send you a personalized IO meter profile. In order to create a support ticket, please go to your Open-E account here: https://www.open-e.com/portal/login/?next=/userportal/

      Reply

  • Michael N /

    29, 07 2015 09:48:03

    we got a win2k12 server with 2 8Gb HBAs cnnected to a HDS G1000. the win-host is mapping virtualized volumes from the G1000 configured as raw-device (not initialized). when we’re starting an iometer-test for example with 60%read 40%write we only see read-transfers on G1000. when starting the same profile with 100%write the IOPS on initialized partitions are crashing down to 40-50 IOPS. is this problem known ?

    Reply

    • Kasia Kolodziej /

      04, 08 2015 07:13:00

      Hey Micheal. Please make sure that in Windows Disk Management the disk is set to online and initialized. Hope this helps!

      Reply

  • Jarred Walton /

    10, 08 2015 09:33:47

    I’m not sure of the cause, but it seems the first test run with IOmeter after using TestFileCreator will give garbage results. For example, on a fast Intel SSD 750 1.2TB drive, the first test I ran on a 128GB test file was a 128K sequential 100% read for six minutes, with a 60 second warmup. The drive supposedly scored 220,000MB/s, or about 10X higher than it should. All the other test results were basically as expected, and when I reran the 128K Seq 100% read again, the result the second time was correct (2272MB/s). I’ve noticed this on basically every drive I’ve tested.

    Reply

  • Naid /

    09, 01 2016 05:02:27

    Hi, how long it takes at Run Time to get a valid result from SSD, especially the result maximum MB/sec. Thanks before. 🙂

    Reply

    • karolina.pletnia /

      14, 01 2016 01:23:58

      Hello Naid! In Open-E DSS V7 IOmeter should show valid results right away. In Open-E JovianDSS in turn, the read results may take a while, even up to a few hours in some cases, before read cache learns the data.

      Reply

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