I'm looking to monitor performance on my Linux servers (which happen to be Centos). What are the best tools for monitoring things in realtime such as:
- Disk Performance I/O, swapping etc..
- CPU Performance
Looking for low level tools, rather than web based tools such as Nagios, Ganglia etc...
n.b. I'd like to know exactly what each tool does rather than just having a list of random toolnames if possible please. Why the tool is a better option than others would be good also.
iostat, sar, top, munin
collectl is a great performance monitor with some unique and advanced features like InfiniBand and Lustre support or environmental and NFS monitoring. Of course it does basic stuff like disk and cpu monitoring, too. Highly recommended!
I've recently release collectl-utils which provided graphing capabilities for collectl data with a web-based tool called colplot. The one key thing with this accuracy. Using gnuplot for the the graphics it's very fast and shows every data point, unlike RRD which 'normalizes' your data. -mark
Doing a Google search for "linux monitoring tools", you find some stuff.
One of the good links found: http://www.cyberciti.biz/tips/top-linux-monitoring-tools.html This article tells you what each tool does, and will give you an idea why one tool is better than another for a particular purpose.
The tools mezgani recommended are listed in that article, except Munin. Munin doesn't seem to be what you are looking for anyway (it is web-based and you specifically said you didn't want web-based).
u can check same of very useful tool of open source.
http://studyhat.blogspot.com/2009/10/linux-system-monitoring-tools-every.html
http://studyhat.blogspot.com/2009/10/linux-limit-cpu-usage-per-process.html
http://studyhat.blogspot.com/2009/10/how-do-i-find-out-linux-cpu-utilization.html
If you want decent historical data graphing, especially for multiple systems, check out Cacti. It requires configuring SNMP on each system (easy).
If you want graph easy your Linux performance, try Bijk.com:
Open source tool with web access and live graphs! http://www.bijk.com
Use atop, that will give you percentage of how much each resource is busy. Also it color codes data and if something is botteling out system resources it will color code those entries.
In CentOS you can install it from EPEL/RPMForge repos.
//Christian
I can see that you are looking for low level tools. But you might want to rethink as I believe performance monitoring is a regular exercise. From my experience I can tell how difficult it can become if you don't use dedicated tools. These are the tools I came across.