Jan 192013

When something goes wrong on your Linux server or desktop, is important to understand which process is taking all the resources, in the past I’ve published some information about top and htop, two great tools to have a general overview of your system with just a glance, but sometimes you need to gather more information of a particular process and for this task the command pidstat is perfect.

Pidstat is a statistics report tool for Linux which is part of the sysstat utilities. The pidstat command is used for monitoring individual tasks currently being managed by the Linux kernel. It writes to standard output activities for every task selected with option -p or for every task managed by the Linux kernel if option -p ALL has been used. Not selecting any tasks is equivalent to specifying -p ALL but only active tasks (tasks with non-zero statistics values) will appear in the report.
You can use PID’s and even regular expressions on the process names to filter them out.
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Dec 202011

Frank Harris-Smith

What exactly is the Linux Kernel and what makes it different than, say Windows or Mac System X? I’m not going to get too deep into the weeds on this one because, quite honestly, I’m not qualified to discuss Kernels beyond the basics. I’m really going to focus on the hardware/software interface aspects of the kernel pros and cons.

First point I’m going to make is that Linux is a kernel, not an Operating System. GNU/Linux is the Linux kernel plus added external software such as a Window Manager like Gnome, utility software, office software and other components to make the make GNU/Linux a complete system for running your computer.
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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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