Slow TTFB for regular domain users, fast for admin accountsRSS

5 replies

Last post Aug 06, 2019 07:26 PM by Rovastar

  • Slow TTFB for regular domain users, fast for admin accounts

    Aug 05, 2019 10:13 PM|manwithahammer|LINK

    Hi.

    I run an IIS server which started exhibiting slow performance recently. We outsource our infrastructure, and after spending 2 hours ruling out all kinds of issues, this is what we discovered:

    1. All "regular" users on the domain see a TTFB overhead of about 4 seconds for all HTTP and XHR requests
    2. If you log in as an admin account (as set up by our third party manager), the overhead disappears
    3. This was behavior replicated on a user desktop and on a domain controller which resides on premises

    To be explicit, TTFB for regular users is 4 seconds slower than for admin users.

    We seem to have ruled out security protocol and cypher issues. Could it be related to proxy settings or or Windows Firewall settings? The network admin says that the difference between regular and admin users relate to things like disabling USB drives and other corporate policies, nothing network related.

    Any help would be appreciated.

    Thanks!

  • Rovastar Rovastar

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    Re: Slow TTFB for regular domain users, fast for admin accounts

    Aug 06, 2019 05:11 PM|Rovastar|LINK

    Are there any caching issues here?

    I'm a little confused by your login situation. Is that logging into a website via application code? Or some NTLM login?

    Can you just hit a static page like plain html or a jpg, etc and do you see the same TTFB?

    Troubleshoot IIS in style
    https://www.leansentry.com/
  • Re: Slow TTFB for regular domain users, fast for admin accounts

    Aug 06, 2019 05:18 PM|manwithahammer|LINK

    No, nothing to do with caching.

    There is no logging in, this is accessing an internal website through a browser, using Windows Authentication. Tested on Chrome and IE, same results.

    It doesn't matter what asset you are accessing, it is consistently the same overhead.

  • Rovastar Rovastar

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    Re: Slow TTFB for regular domain users, fast for admin accounts

    Aug 06, 2019 05:43 PM|Rovastar|LINK

    Local windows auth or a domain? Maybe it issues contacting the DC in  a timely manner.

    Troubleshoot IIS in style
    https://www.leansentry.com/
  • Re: Slow TTFB for regular domain users, fast for admin accounts

    Aug 06, 2019 05:44 PM|manwithahammer|LINK

    We only use domain accounts.

    But why would an admin domain account not have that issue?

  • Rovastar Rovastar

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    Re: Slow TTFB for regular domain users, fast for admin accounts

    Aug 06, 2019 07:26 PM|Rovastar|LINK

    Difficult to say maybe there is a different login stuff/privileges for those non-admin accounts. I would look into at the DC end and see if it is slow there and look for other things that are slower for non-admin accounts there at login/etc

    Troubleshoot IIS in style
    https://www.leansentry.com/