Keep getting message Mutex cleaned, application could not launch. on a cgi web app

  1. 8 months ago

    Leonidas B

    26 Dec 2018 Macaé, RJ, Brazil

    Hello,

    Every once in a while my users get the message "Mutex cleaned, application could not launch." from a cgi web app I wrote. I did some research in the forum and already isolated a potential issue with MySQLCommunityServer by encapsulating it on a Critical Section.

    Whenever it happens, it is "easily" solved by killinh the app over SSH.

    What else can be causing this issue?

    My web app is gaining momentum, with several simultaneous users. Can't afford to have it breaking like that.

    Please advise!

  2. 3 months ago

    James N

    Jun 3 Pre-Release Testers, Xojo Pro Christchurch New Zealand

    HI Leonidas
    Did you work out what was causing your crash
    ie Keep getting message Mutex cleaned, application could not launch. on a cgi web app.
    I'm getting the same and it takes down the whole virtual server,

    Cheers James

  3. Greg O

    Jun 4 Xojo Inc

    @James N-Plank I'm getting the same and it takes down the whole virtual server,

    While related, I bet this is not really the cause-effect you think it is. Monitor memory and CPU usage on your server over time and I bet what you’ll find is that one of your apps is leaking memory uncontrollably and once the system runs out of RAM, it just crashes. Modern systems that use SSD drives usually have virtual memory disabled and when you’re out of RAM, that’s it.

  4. James N

    Jun 4 Pre-Release Testers, Xojo Pro Christchurch New Zealand

    Thanks Greg
    the system was literally only up for 5 minutes.
    it took out all the docker containers when it died.
    However I will take note and really look at ram usage.
    Appreciate the heads up.

    Just for you and your team
    Thanks for Xojo

    This would be a nightmare web app to write in most other environments.
    I’m a one man band yet I can create anything any other development company can. And a lot faster.

    Cheers

  5. Leonidas B

    Jun 4 Macaé, RJ, Brazil

    Hello @James N-Plank !

    The issue went away some time ago. I really don't know what solved it exactly (sorry).

    What I have done so far that might have helped:

    • Make sure all possible leaks were contained (closing reocrdsets after using them, etc.);
    • Take very special care of database connections (one per Session) and properly closed on logout
    • Implemented a TimeOut feature to the app, that closes it, turning all Session objects to nil and showing a regular HTMl page to the user
    • Implemented @Michel B 's approach of 3 AM kill procedure using CRON
    • Adopt @ChristianSchmitz 's simple web balancing technique

    Hope it helps!

or Sign Up to reply!