Linux

Linux Performance Analysis and Tools

I just watched though Linux Performance Analysis and Tools: Brendan Gregg’s Talk at SCaLE 11x. It is an interesting talk is about Linux Performance Analysis and Tools: specifically, observability tools and the methodologies to use them. It goes through over 20 Linux performance analysis tools, including advanced perf and DTrace for Linux, showing the reasons

Open files in Linux

lsof is a very useful Linux command, which can be used to report a list of all open files and the processes that opened them. lsof is very useful in debugging because files in the Linux/Unix system include disk files, named pipes, network sockets and devices opened by all processes. lsof name comes from “list

Linux TTY

The TTY subsystem is central to the design of Linux, and UNIX in general. The TTY system in Linux is a throwback to when computers first because interactive in real-time,but is still very much relevant today. Unfortunately, its importance is often overlooked, and it is difficult to find good introductory articles about it. The TTY

Shell script testing

Some time ago I had to test several shell scripts how they affect the running environment on Linux. I ended up writing this simple script to help testing. This example script runs testsubject.sh script, and shows changes to enviroment variables the script causes. !/bin/bash # # Script to handle file sending to server # env

fsniper

In Linux system almost everything is a file. fsniper is a tool that monitors a given set of directories for new or modified files then applies rule based scripts. It is a very useful tool for handling files automatically when they are created. I have used if for many applications. According to fsniper documentation fsniper

Redundancy with Raspberry Pi

Linux Journal has an interesting article series on building redundant systems out of Raspberry Pis. Even though an individual Raspberry Pi is not that redundant, two Pis configured as redundant systems are. Two Pi R articled describes how to set up two Raspberry Pis as a fault-tolerant file server using the GlusterFS clustered filesystem. It

XVI32 freeware hex editor

When I need to view and sometimes edit binary files I typically use XVI32 software for it. XVI32 is a freeware hex editor running under Windows. It has data inspector to view decoded numbers and has a built-in script interpreter. XVI32 is a portable application, i.e. no setup program is needed, you can run XVI32

Linux networking articles

Linux Journal has published several interesting articles on Linux networking. Here are some of the most interesting of them. Queueing in the Linux Network Stack tells that packet queues are a core component of any network stack or device. They allow for asynchronous modules to communicate, increase performance and have the side effect of impacting