Page 2 of 2 FirstFirst 12
Results 11 to 11 of 11

Thread: I need help in choosing the right Raid Configuration.

  1. #11
    nooto is offline Member
    Join Date
    Oct 2012
    Posts
    10
    Rep Power
    2

    Default

    Hi!

    One more thing to note: to get proper results with the write tests you should write a file at least 2xYour_RAM_size. At least this is what bonnie or iozone does. Otherwise you'll get incorrect results, as probably the ones posted above. In your case it's a little bit harder to do if you have 64 Gigs of ram. I have only 7.

    And if you are testing this on Thin_provisioned/lazy_zeroed disks on ESXi, then the result will vary greatly for the first time and second time writing the same block. As you can't easy tell when it's writing the block for the first or for the second time it's hard to get the correct results on Thin provisioned disks.

    Code:
    root@mail:/opt/test# time sh -c "dd if=/dev/zero of=/opt/test/ddfile1 bs=8k count=17500 && sync"
    17500+0 records in
    17500+0 records out
    143360000 bytes (143 MB) copied, 0.175012 s, 819 MB/s
    
    real    0m1.903s
    user    0m0.000s
    sys     0m0.244s
    
    root@mail:/opt/test# time sh -c "dd if=/dev/zero of=/opt/test/ddfile2 bs=8k count=175000 && sync"
    175000+0 records in
    175000+0 records out
    1433600000 bytes (1.4 GB) copied, 2.50452 s, 572 MB/s
    
    real    0m34.472s
    user    0m0.084s
    sys     0m2.540s
    
    root@mail:/opt/test# time sh -c "dd if=/dev/zero of=/opt/test/ddfile3 bs=8k count=1750000 && sync"
    1750000+0 records in
    1750000+0 records out
    14336000000 bytes (14 GB) copied, 146.679 s, 97.7 MB/s
    
    real    2m28.665s
    user    0m0.580s
    sys     0m42.463s
    Last edited by nooto; 10-11-2012 at 05:20 AM. Reason: Mistakes :}

Page 2 of 2 FirstFirst 12

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Choosing Pdf program
    By guyweisz in forum General Questions
    Replies: 0
    Last Post: 12-14-2011, 04:13 AM
  2. Raid configuration for best performance?
    By amagdic in forum Administrators
    Replies: 12
    Last Post: 12-09-2009, 10:20 AM
  3. RAID Re-configuration, Easiest Way To Move Zimbra?
    By thunder04 in forum Installation
    Replies: 6
    Last Post: 12-03-2009, 04:43 PM
  4. Optimum RAID drive configuration
    By rusty in forum Administrators
    Replies: 1
    Last Post: 06-04-2009, 04:12 PM
  5. How to choosing incoming/outgoing domains
    By tilinhonh in forum Administrators
    Replies: 2
    Last Post: 08-01-2007, 05:22 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •