iotop in an application that enables you to monitor the hard drive write and reads for individual processes, much like in the same way top monitors cpu/memory usage. iotop can easily be installed in Ubuntu, or other Debian based distros by entering this command in a terminal:
sudo apt-get install iotop
iotop can only run under a Linux 2.6.20 or later kernel built with the CONFIG_TASKSTATS, CONFIG_TASK_DELAY_ACCT, CONFIG_TASK_IO_ACCOUNTING and CONFIG_VM_EVENT_COUNTERS build config options on.
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