System Monitoring >>> Which of the following utilities can be used to monitor I/O activity? >>> Linux for Developers
iotop must be run by a root user and directly displays I/O usage on the system, interactively refreshing every few seconds.
iostat gives detailed information about current I/O activity and can report at a specified interval, as many times as desired.
sar gives comprehensive system activity reports, including but not limited to I/O activity.
vmstat reports a lot of information about not only I/O activity, but memory and other areas.
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uptime shows how long the system has been running.
top is a frequently used interactive and constantly updating tool to see what processes running on the system and what resources they are using, sorted by factors that can be chosen.
ps is a frequently used tool that lists some or all processes on the system and shows their state and resource allocation.
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vmstat will show current used and free memory, will show activity interactively specifying interval and count, such as vmstat 2 6
free gives basic statistics about memory used, free, in cache, in swap, etc.
pmap is process map: it shows detailed use of the memory used for a given process.
The command line tools are generally identical on all Linux-based systems.
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gnome-system-monitor is associated with the GNOME desktop, but can be installed on almost any Linux distribution.
ksysguard is associated with the KDE desktop, but can be installed on almost any Linux distribution.
