[BUG] pmm-ras produces high CPU load




  • Avatar
    Unknown User

    For those as confused as I was when researching the process pmm_ras process this a related thread is here in the forum -


    Indicates this process is actually linked to Plesk migration manager.

    I'd recommend checking /var/log/plesk/PMM/migration.log to see what it's up-to, in my case the CPU load wasnt super high, but had been runnign for a while and that's what was suspect - however since this is linked to the backup process helps explain that this is most likely normal behaviour - in my case CPU wasnt as high as illustrated here but it was one of the top processes for many hours.

    Comment actions Permalink
  • Avatar
    Alexandr Redikultsev


    Thank you for sharing you experience.

    Comment actions Permalink
  • Avatar

    I've had my share of this problem as well. While backup compression was active I had extremely high CPU that would prevent sites from loading. After switching it off I ended up with high I/O usage at periods which would slow them down. I'm on a powerful VPS however the CPU and DISK usage was very high. Even on a dedicated server the performance drop is noticeable while pmm-ras is running. I was told by support to monitor this thread here.

    I've added a suggestion in plesk uservoice regarding backup priorities which should help.


    I'm hoping more people will vote on that

    Currently I've had to use 3 separate cron jobs to lower the cpu and I/O priority of backups

    • pmm-ras 
    • pigz
    • tar



    Comment actions Permalink

Please sign in to leave a comment.

Have more questions? Submit a request