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Azure storage performance and management RRS feed

  • Question

  • Hello,

    Could someone help me to understand following topics.

    First of all I am on a trial account mode, maybe this is my issue, but I ma not sure yet.

    I installed a Linux VM (OpenLogic CentOS6.3). I attached an empty data disk. Both disks OS and Data created on the same storage account. I tested IO performance using dd Linux tool (I understand that this is not a very relevant test especially for database VM, but still can give me an idea which disk is faster). The result was pretty similar from both disks. Here are my questions.

    Azure storage performance:

    ===================

    Is it true that Azure storage is SSD based storage?

    Why the IO write performance on OS disk faster then on Data disk? I have red somewhere that it should be opposite. On the other hand reads are similar.

    OS disk writes:

    dd if=/dev/zero of=speedtest bs=64k count=3200 conv=fdatasync oflag=direct

    3200+0 records in
    3200+0 records out
    209715200 bytes (210 MB) copied, 11.457 s, 18.3 MB/s

    Data disk writes:

    dd if=/dev/zero of=speedtest bs=64k count=3200 conv=fdatasync oflag=direct

    3200+0 records in
    3200+0 records out
    209715200 bytes (210 MB) copied, 22.9221 s, 9.1 MB/s

    OS disk reads:

    dd if=speedtest of=/dev/null bs=64k count=24000

    3200+0 records in
    3200+0 records out
    209715200 bytes (210 MB) copied, 0.463566 s, 452 MB/s

    Data disk reads:

    dd if=speedtest of=/dev/null bs=64k count=24000

    3200+0 records in
    3200+0 records out
    209715200 bytes (210 MB) copied, 0.493757 s, 425 MB/s

    Azure storage management:

    ====================

    I have red in Azure documentation somewhere that it is always good idea to attach data disk from a separate storage account. When I tried to attach empty disk I didn't have an option to choose a different storage account. Everything is created on the same storage account where VM OS disk was created. Is it possible to archive that?


    • Edited by UserAzure Monday, June 24, 2013 9:09 PM
    Monday, June 24, 2013 9:08 PM

Answers