May 192014
 

Dstat is a versatile replacement for vmstat, iostat, netstat and ifstat. Dstat overcomes some of their limitations and adds some extra features, more counters and flexibility. Dstat is handy for monitoring systems during performance tuning tests, benchmarks or troubleshooting.

Dstat allows you to view all of your system resources in real-time, you can eg. compare disk utilization in combination with interrupts from your IDE controller, or compare the network bandwidth numbers directly with the disk throughput (in the same interval).

Dstat gives you detailed selective information in columns and clearly indicates in what magnitude and unit the output is displayed. Less confusion, less mistakes. And most importantly, it makes it very easy to write plugins to collect your own counters and extend in ways you never expected.

Dstat’s output by default is designed for being interpreted by humans in real-time, however you can export details to CSV output to a file to be imported later into Gnumeric or Excel to generate graphs.
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Oct 042011
 

Cgroups is present in the official Linux kernel 2.6.24 (late 2007), still he’s not much know or used (at least for what i know).
In this article I’ll give you an overview of this powerful Linux tool to control how much CPU, memory, disk I/O or network I/O each process or user can use in your server.

So in short cgroups it’s a feature to limit, account and isolate resource usage (CPU, memory, disk I/O, etc.) of process groups.
Let’s see how.

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