Uninterruptable processes

The processes which are trying to access I/O device may me uninterruptable when that I/O device is very busy/unavailable. For example suppose a process is accessing an NFS shared file and if the NFS server is stopped,  the process state becomes “Uninterruptable”. That means it cannot be killed. To kill such processes either the machine has to reboot or the process should get the unavailable resource back.

The following command lists the uninterruptable processes.

ps axo stat|grep -i D

By piping the above output to wc and cut you will get the count of uninterruptable process.

ps axo stat|grep -i D|wc|cut -d ” ” -f1-10