Logical processors

  • Comments posted to this topic are about the item Logical processors

    Igor Micev,
    My blog: www.igormicev.com

  • This was removed by the editor as SPAM

  • Really? Or are you just kidding? :w00t:

    What was the question about?

    Guessing whether it is physical/virtual machine or capacity limits?

    Or was it about lower edge of maximum capacity limits? :blink:

    Either way explanation is flawed - virtual machine can use 16 virtual processors and it does not matter whether they are hyper-threaded or not (virtual machine is not aware of that).

    In this case logical processors are taken for virtual processors but that is not always true.

  • Interesting question, thanks.

    Need an answer? No, you need a question
    My blog at https://sqlkover.com.
    MCSE Business Intelligence - Microsoft Data Platform MVP

  • dawryn (9/21/2016)


    Really? Or are you just kidding? :w00t:

    What was the question about?

    Guessing whether it is physical/virtual machine or capacity limits?

    You don't have to guess, it clearly states "You have a physical server with 12 physical cores placed in two sockets..."

    Either way explanation is flawed - virtual machine can use 16 virtual processors and it does not matter whether they are hyper-threaded or not (virtual machine is not aware of that).

    For the virtual machines it is different.There, the maximum number of logical processors the Standard edition of 2014 can use is 16.

    At VMs, virtual processors are logical processors, that's all. What is not clear here?

    [/quote]

    In this case logical processors are taken for virtual processors but that is not always true.

    Please tell here when it's not always true. That's the point of the QotT in this site.

    Igor Micev,
    My blog: www.igormicev.com

  • Igor Micev (9/21/2016)


    dawryn (9/21/2016)


    What was the question about?

    Guessing whether it is physical/virtual machine or capacity limits?

    You don't have to guess, it clearly states "You have a physical server with 12 physical cores placed in two sockets..."

    It also clearly states "SQL Server 2014 Standard edition is installed on the server." Here the guess comes in. Or is that something taken? If positive - for whom?

    Either way explanation is flawed - virtual machine can use 16 virtual processors and it does not matter whether they are hyper-threaded or not (virtual machine is not aware of that).

    For the virtual machines it is different.There, the maximum number of logical processors the Standard edition of 2014 can use is 16.

    At VMs, virtual processors are logical processors, that's all. What is not clear here?

    Do you mean: "In a virtualized environment, the compute capacity limit is based on the number of logical processors, not cores, because the processor architecture is not visible to the guest applications." discards usage of virtual processor in communication?

    What about hyper-threading OFF (see below)?

    In this case logical processors are taken for virtual processors but that is not always true.

    Please tell here when it's not always true. That's the point of the QotD in this site.

    It is possible: "One can enable or disable hyperthreading using a BIOS setting for the processor during the BIOS setup..."

  • Boh, I don't understand:

    The SQL Server 2014 Standard Edition can use up to 16 physical cores. If hyper-threading is enabled on a 16-core server, then there are 32 logical processors, and SQL Server will use all of them.

    Here, it states clearly that SE can use up to 32 LOGICAL PROCESSORS.

    So, I answered "24 logical processors because hyper-threading is enabled". Where's the catch?

  • Carlo Romagnano (9/21/2016)


    Boh, I don't understand:

    The SQL Server 2014 Standard Edition can use up to 16 physical cores. If hyper-threading is enabled on a 16-core server, then there are 32 logical processors, and SQL Server will use all of them.

    Here, it states clearly that SE can use up to 32 LOGICAL PROCESSORS.

    So, I answered "24 logical processors because hyper-threading is enabled". Where's the catch?

    H Carlo,

    I see that I've done a mistake checking the right answer in the question. The correct answer is 24 logical processors.

    How to inform the administrator to correct this?

    Igor Micev,
    My blog: www.igormicev.com

  • Igor Micev (9/21/2016)


    Carlo Romagnano (9/21/2016)


    Boh, I don't understand:

    The SQL Server 2014 Standard Edition can use up to 16 physical cores. If hyper-threading is enabled on a 16-core server, then there are 32 logical processors, and SQL Server will use all of them.

    Here, it states clearly that SE can use up to 32 LOGICAL PROCESSORS.

    So, I answered "24 logical processors because hyper-threading is enabled". Where's the catch?

    H Carlo,

    I see that I've done a mistake checking the right answer in the question. The correct answer is 24 logical processors.

    How to inform the administrator to correct this?

    Send a message to Steve.

  • Interesting question. Cheers

  • Carlo Romagnano (9/21/2016)


    Igor Micev (9/21/2016)


    Carlo Romagnano (9/21/2016)


    Boh, I don't understand:

    The SQL Server 2014 Standard Edition can use up to 16 physical cores. If hyper-threading is enabled on a 16-core server, then there are 32 logical processors, and SQL Server will use all of them.

    Here, it states clearly that SE can use up to 32 LOGICAL PROCESSORS.

    So, I answered "24 logical processors because hyper-threading is enabled". Where's the catch?

    H Carlo,

    I see that I've done a mistake checking the right answer in the question. The correct answer is 24 logical processors.

    How to inform the administrator to correct this?

    Send a message to Steve.

    I've written a message to Steve to correct the question's answer. It's my mistake. I'm sorry for that.

    Thanks for the remark!

    Igor Micev,
    My blog: www.igormicev.com

  • Still a decent question as I had to look up the difference in the editions.

    I learned something from that and the the comments in the post.

    Thank you for submitting it.

  • Although incorrect, the answer does highlight an interesting difference between a virtual machine and a physical machine where it comes to logical CPU usage which I never knew about, so thanks for that!

  • Apologies for the wrong checkbox. I thought I had set this correctly, but I may have clicked the wrong answer item.

    Points have been awarded back to this time.

  • Thanks Igor for this question. It made me diligently googled and study

    SQL Server Hardware e-book from Glenn Bery and more. Then I found the correct

    answer in an article on Dan Guzman's Blog, which is listed in the references.

    Yeah, you authors of the QotD don't have it easy. 🙂

Viewing 15 posts - 1 through 15 (of 37 total)

You must be logged in to reply to this topic. Login to reply