IIS 10 App Pools using high memoryRSS

5 replies

Last post May 10, 2019 07:30 AM by Able

  • IIS 10 App Pools using high memory

    May 07, 2019 06:39 PM|ccoggins|LINK

    Good afternoon,

    I am having a really weird issue and I have been trying to Google answers for the last few days and nothing I am coming up with is the same as what I am encountering. 

    It is also kind of hard to explain:
    So here is the low down -
    I have multiple web servers hosting a bunch of different user portals/web sites. 

    Each of my servers has 2x web server VM's that I use to load balance the web portals. 

    All of my servers are that have web servers are running perfectly normal except for 1 server.

    This one server that is causing me problems has give or take 75 App Pools on it.
    Process Hacker is telling me almost every single one of these app pools is doing something. They are also using upwards of 180MB of memory (Which is normal for a site that is actually in use). However, there is no CPU load on this and when I view a site there is no active requests being sent to the site.

    On any of my other web servers process hacker shows little to no activity on all the sites and they hover around 4mb of memory being used.

    This is what PH looks like on my server using a bunch of memory:
    https://imgur.com/OEgIhQ5


    This is what my behaving servers look like:

    https://imgur.com/0I2Hrw6

    The first photo is the w3wp process just being active and using a ton of memory, but nothing is actually going on.
    It seems to be almost all the app pools are "pretending" to do things.
    I have rebooted this server a couple of times at night to see if it fixes the issue, but as soon as it comes back on all the app pools just start running and chewing up memory. 

    I have also just tried killing the w3wp process and also stopping and restarting each app pool individually with no luck.

    Thank you for any help you might be able to provide.

  • Re: IIS 10 App Pools using high memory

    May 07, 2019 10:30 PM|lextm|LINK

    IIS itself does not use much memory. What are the web apps? You need language specific memory profiling tools to analyze memory usage so that issues can be identified.

    Lex Li
    https://lextudio.com
    ---------------------------
    This posting is provided "AS IS" with no warranties, and confers no rights.
  • Re: IIS 10 App Pools using high memory

    May 08, 2019 02:04 PM|ccoggins|LINK

    The applications running on the website are just a hosted web portal to allow customers to clock in and out for work.

    There is also a portal that allows supervisors to check their employee punches. 

  • Re: IIS 10 App Pools using high memory

    May 09, 2019 09:27 AM|Able|LINK

    Hi ccoggins ,

    According to your description, firstly, I suggest that you could track currently running IIS worker processes.

    Here are 6 Common Causes of IIS Worker Process High CPU.There are a lot of reasons that you can be seeing w3wp.exe high CPU usage.

    1.Inefficient .NET code that needs to be optimized
    2.High error rates within your ASP.NET web application
    3.Increase in web traffic causing high CPU
    4.Problems with application dependencies
    5.Garbage collection
    6.Requests getting blocked or hung somewhere in the ASP.NET pipeline

    Here is the link , i hope it could help you.

    https://stackify.com/w3wp-high-cpu-usage/

    Else you can configure IIS to recycle the app pool at fixed intervals, fixed number of requests, at specific time or at certain memory thresholds.

    1. 1.Run inetmgr
    2. 2.In the Connections pane, expand the server name, and then click Application Pools
    3. 3.Select desired application pool
    4. 4.In the Actions pane, click Recycling

    Here is the link , I hope it could help you.

    https://serverfault.com/questions/259327/iis7-how-to-handle-application-pools-which-uses-too-much-memory-or-cpu

    Best Regards

    Able

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  • Re: IIS 10 App Pools using high memory

    May 09, 2019 05:12 PM|ccoggins|LINK

    Thank you for the response Able,

    I am not really running into a High CPU Usage Scenario.
    It is a High Memory issue - actually it's not even really that.
    It is just the fact that all of the Application Pools are active when they should not be.

    So they are using (the correct) amounts of memory as if they were being used by my users, but there is no way that all 70 App Pools are in use. So the majority of them should be sitting at around 4-5MB vs 100-200MB.

    I have restarted the application pools aka recycled them and as soon as they come back they all jump back up to 100-200MB.
    I also do not believe this is a memory leak because I would see this same issue happening on the other 8 Web Servers all running the same code.

  • Re: IIS 10 App Pools using high memory

    May 10, 2019 07:30 AM|Able|LINK

    Hi ccoggins 

    According to your description, I suggest that you could check the iis logs so that you could see what happened after you started iis.

    Here is the link for how to find logs

    https://stackoverflow.com/questions/6426375/where-can-i-find-the-iis-logs

    Best Regards

    Able

    Please remember to click "Mark as Answer" the responses that resolved your issue.
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