1. Please take a little time for this simple survey! Thank you for participating!
    Dismiss Notice
  2. Dear Pleskians, please read this carefully! New attachments and other rules Thank you!
    Dismiss Notice
  3. Dear Pleskians, I really hope that you will share your opinion in this Special topic for chatter about Plesk in the Clouds. Thank you!
    Dismiss Notice

CPU stuck on WAIT, and apache and mysql hanged...

Discussion in 'Plesk for Linux - 8.x and Older' started by andor, Sep 25, 2008.

  1. andor

    andor Guest

    Hi everyone!

    I set up a LAMP server with a Plesk control panel, and from time to time its getting stuck with the CPU use 100% in WAIT state.

    MySQL queries take ages to finish, and the http queries don't ever finish to stuck in the queue, so finally I'm getting like 100 or 200 http processes, and a stuck MySQL.

    With a lot of difficulty I log on to the server, restart the apache and the mysql server, and it begins to be responsive again.

    I've been checking the slowqueries on mysql, and I see some, but are very simple ones, so I think they're going slow because the server is stuck on "WAIT", and I think I don't see any unusual quantity of queries on the server.

    How can I check what are my proccesses WAITing for? Is my hard disk doing something weird, maybe it's dying and when reading or writing on some position it gets stuck?

  2. Amin Taheri

    Amin Taheri Golden Pleskian Plesk Certified Professional

    Jul 5, 2007
    Likes Received:
    Seattle Area
    you can get the PID of the process and try and do an lsof -p <pid> and see if you can see what its using. You can also set the hung_task_timeout_secs sysctl setting and see if that helps.