Description
nmon collects the following operating system statistics: * CPU and CPU threads Utilisation * CPU frequency for servers or virtual machines that can alter their clock rate * GPU stats including utilisation, MHz and temperatures * Physical and Virtual Memory use * Disk read & write and transfers plus service time and wait times * Disk Groups - decided by the user * Swap and Paging * Network read & write and transfers * Local File-systems * Network File-system (NFS) * Top Processes by CPU use, Memory size and I/O rates * Kernel stats including Run Queue, context-switch, fork, Load Average & Uptime * Large and Huge memory pages * NFS (Networked File System) * Virtual Machine stats (depending on the hardware) — useful for Linux running KVM to host virtual machines * Resources in the Server and virtual machine *nmon -h lists the details
* To start collecting the stats to a file use the -f or -F option
When viewing in on-screen mode the stats displayed are controlled by the user using single letter toggles. For example, "c" to show CPU and then another "c" will switch the CPU stats off. Use h to display a list of the options.
When saving the stats to a file, there is a common default set of stats and then users can request more using command line options. Use nmon -? to display all the options.
The output file can be analyzed with nmonanalyzer.
History
The original nmon version was for the IBM AIX operating system (Release 4.3 and above) and was freely downloadable binary format only tool from the IBM AIX wiki. * Later a version was written for the Linux operating system running on IA-32, x86, x86_64, IBM RS/6000 and POWER processors, Mainframe and ARM (including Raspberry Pi). nmon for Linux was released by IBM asFeatures
* There are two runtime modes available: # In ''Online Mode'' it uses curses for efficient screen handling, which updates the terminal frequently for real-time monitoring. # In ''Capture Mode'', the data is saved to a file in CSV format for later processing and graphing. The file also includes important configuration details that are useful for recommending tuning. * nmon concentrates on performance information for the performance tuner and in a concise layout to aid understanding. This includes CPU, memory, disks, adapters, networks, NFS, Kernel statistics, File-systems, Workload Manager (AIX), Workload Partitions (AIX) and Top Processes. * nmon includes support for older AIX releases, Linux running on x86, POWER and Mainframe platforms and other Linux supporting hardware.Screenshots
Alternatives
On AIX, there is thetopas command that can output reports to a file but this is not in a format that can be used easily as a source for a spreadsheet or web tools like RRDtool.
On Linux, there is the top
A spinning top, or simply a top, is a toy with a squat body and a sharp point at the bottom, designed to be spun on its vertical axis, balancing on the tip due to the gyroscopic effect.
Once set in motion, a top will usually wobble for a few ...
command which is good for CPU and processes but does not cover disks and networks. For disk I/O, the iostat
iostat (''input/output statistics'') is a computer system monitor tool used to collect and show operating system storage input and output statistics. It is often used to identify performance issues with storage devices, including local disks, or ...
command can give you the details and dstat can be used to produce text data, even in comma separated value format, which is quite suitable for spreadsheet programs.
References
External links
* {{official website, http://nmon.sourceforge.net/