Wait_type null

  • Hi,

    I' have query running an avg 14 seconds every time it gets executed and I'm trying to find what that session is waiting for.

    I'm using sp_whoisactive procedure and I'm seeing wait_info as NULL. What does that mean? how to find what this session is waiting for?

    Wait_type_Null

  • Thanks for posting your issue and hopefully someone will answer soon.

    This is an automated bump to increase visibility of your question.

  • It means it's not waiting on anything.  Since you're doing more than 4 million reads (more than 31GB of I/O), you likely have some performance challenged code that needs to be reworked.

    --Jeff Moden


    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

    Change is inevitable... Change for the better is not.


    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)

  • Thanks Jeff,

    How did you convert 4 million reads to 31 GB of IO ?

  • A logical read is an 8K page. Divide the reads by 128 to get the MB. Divide by 1024 to get GB.

    Sue

  • gana79950 wrote:

    Thanks Jeff,

    How did you convert 4 million reads to 31 GB of IO ?

    Sue_H wrote:

    A logical read is an 8K page. Divide the reads by 128 to get the MB. Divide by 1024 to get GB.

    Sue

    Just to clarify what Sue wrote... dividing the number of pages by 128 will return the number of MB the pages represent.  You would have to divide THAT number of MB by 1024 to get GB.  Or, you can just divide by 131,072, which is 128*1024.

    So, 4,075,902 / 131,072 = ~31.096664GB.

    --Jeff Moden


    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.

    Change is inevitable... Change for the better is not.


    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)

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