IIS does not assign requests correctly to worker processesRSS

3 replies

Last post Feb 27, 2020 05:37 AM by Yuk Ding

  • IIS does not assign requests correctly to worker processes

    Feb 26, 2020 08:56 AM|motobit|LINK

    2 sockets, 12 core, Win 2012 R2, IIS/7.5, ASP, Helicon URL rewrite
    App pool with 10 worker processes
    ProcessorThreadMax 20

    IIS works normaly and assigns requests equally to worker processes for some time - minutes, hours. But after this, IIS use only one process, the process is overloaded (100th of requests in queue, most of them active), other worker processes in the app pool are almost idle.

    IIS response time is in 10th of seconds.

    Recycle of the pool solves the situation, but only for some minutes, hours. And then again.

    Any suggestion?


  • Re: IIS does not assign requests correctly to worker processes

    Feb 26, 2020 04:49 PM|carehart|LINK

    That would be odd, at least with default settings. But you could have configured something that could be influencing it, or you may have some unusual problem.

    Let's start with some clarifications:

    • when you say "10th of seconds", do you really mean "10s of seconds"? I'm guessing so, from when you said "100th of requests in queue"
    • when you say there are hundreds in queue, can you confirm how you are observing that? with perfmon? or with the "view requests" feature on that "worker process monitor" page you are looking at, which you see if you right-click on an app pool instance? (If you do not see that option, it's that you have not enabled the "request monitor" feature when setting up IIS.)
    • or since your username is motobit, are you the same motobit whose company offers the old iistracer tool (which many folks used before IIS added this request monitoring feature, but sadly seems not to have been updated since IIS 7)? If so are you using that?
    • If you are finding requests piled up in the request monitor, are you going further to enable "failed request tracing" (another IIS feature that is not enabled by default)? That may tell you WHERE and why requests are hung up, which may help explain how so many are, and so may be the best first focus for you
  • Re: IIS does not assign requests correctly to worker processes

    Feb 26, 2020 05:00 PM|lextm|LINK

    The actual load distribution is controlled deep down inside IIS, so your only hope is to go through Microsoft support by opening a support case via http://support.microsoft.com

    However, you should seriously consider a multi server setup load balancing cluster. The web garden approach (multi process application pool) is not widely used.

    Lex Li
    Affordable IIS Consulting Services at https://support.lextudio.com/services/consulting.html
    This posting is provided "AS IS" with no warranties, and confers no rights.
  • Re: IIS does not assign requests correctly to worker processes

    Feb 27, 2020 05:37 AM|Yuk Ding|LINK

    Hi motobit,

    This issue could be complicated. You may need to capture dump file and etl log. So we can check what happened there. It is also important to capture the last request before other worker process down. 

    As lex said, if this is making business impact, please open a support ticket and involve professional engineer for help.

    Best Regards,

    Jokies Ding

    Yuk Ding

    MSDN Community Support
    Please remember to "Mark as Answer" the responses that resolved your issue.