This post summarizes Linux Kernel new features, bugfixes and changes in Linux 4.19.178 Release. Linux 4.19.178 Release contains 248 changes, patches or new features. In total, there are 239,909 lines of Linux source code changed/added in Linux 4.19.178 release compared to Linux 4.19 release. To view the source code of Linux 4.19.178 kernel release online,
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Tag: debug
Linux Kernel 4.14.223 Release
Posted onThis post summarizes Linux Kernel new features, bugfixes and changes in Linux 4.14.223 Release. Linux 4.14.223 Release contains 176 changes, patches or new features. In total, there are 277,921 lines of Linux source code changed/added in Linux 4.14.223 release compared to Linux 4.14 release. To view the source code of Linux 4.14.223 kernel release online,
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Linux Kernel 5.4.102 Release
Posted onThis post summarizes Linux Kernel new features, bugfixes and changes in Linux 5.4.102 Release. Linux 5.4.102 Release contains 338 changes, patches or new features. In total, there are 160,715 lines of Linux source code changed/added in Linux 5.4.102 release compared to Linux 5.4 release. To view the source code of Linux 5.4.102 kernel release online,
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Linux Kernel: Add support for using a MAX3421E chip as a host driver
Posted onThis change “Add support for using a MAX3421E chip as a host driver.” (commit 2d53139) in Linux kernel is authored by David Mosberger <davidm [at] egauge.net> on Mon Apr 28 22:14:07 2014 -0600. Description of “Add support for using a MAX3421E chip as a host driver.” The change “Add support for using a MAX3421E chip
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Installing R and RStudio Server in Ubuntu Linux 20.04
Posted onR is a language and environment for statistical computing and graphics, providing a wide variety of statistical and graphical techniques. The R environment is open source software under GPL. R has rich software packages and is widely used for statistical analysis. RStudio Server is an R integrated development environment (IDE) that provides many useful features
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Linux Kernel 4.19.70 Release
Posted onThis post summarizes new features, bugfixes and changes in Linux kernel release 4.19.70. Linux 4.19.70 Release contains 95 changes, patches or new features. In total, there are 101,521 lines of Linux source code changed/added in Linux 4.19.70 release compared to Linux 4.19 release. To view the source code of Linux 4.19.70 kernel release online, please
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Bash Learning Materials
Posted onBash (GNU Bourne-Again SHell) the default shell for many Linux distributions. It is very common for scripting languages in Linux. Bash is easy and straightforward for writing small tools. However, as most tools, it has its grammars that could easily cause bugs if they are not used correctly. Here I summarize a list of good
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gdb like step by step debugger for Python
Posted onAny good debugger for Python that is like gdb so that the code can be executed step by step for debugging purpose? You might check pdb. You can debug a program such as prog.py by invoking it through pdb: python -m pdb prog.py Common gdb commands can be found in pdb: (Pdb) h Documented commands
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How to Debug a Bash script?
Posted onHow to debug a Bash script if it has some bugs? Common techniques like printing varibles out for checking apply for bash too. For bash, I also use 2 bash-specific techniques. Use errexit option Run the script with -e option like bash -e your-script.sh or add set -o errexit to the beginning of the script.
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How to output function stack in Linux Kernel
Posted onIn Linux Kernel, we usually trace/debug what kind of events will trigger the phenomena we find in the system. For example, what kind of event will trigger the fact that the timeslice of one process will be very short. In order to solve these kind of problems, we need to output the function stack. Currently,
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How to debug media print view of Web page in Firefox?
Posted onHow to debug the media print view set by @media print {} in CSS of Web pages in Firefox? In firefox, after opening the Web page, First, hit “Shift + F2” to open the “Developer Toolbar” at the bottom. Second, in the “Developer Toobar”, input media emulate print and Firefox will show the print view
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Un-exporting an Exported Variable in Bash in Linux
Posted onHow to un-export an imported variable in Bash on Linux? For example, first, I export a variable MODE like export MODE=debug but I want to unexport the MODE (not turn to be `””`, should be truly non-defined). You can export -n MODE or unset MODE For your reference (from the [`bash` manual](https://www.systutorials.com/docs/linux/man/1-bash/)): export [-fn] [name[=word]]
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How to debug/check network-related driver information on Linux?
Posted onHow to debug/check network-related driver information on Linux? Several commands/tools that you may find usefull: Messages: dmesg grep NetworkManager /var/log/messages lshw: list hardware lshw -c network lsusb: list USB devices lsusb rfkill: enabling and disabling wireless devices rfkill unblock all rfkill event iwconfig: configure a wireless network interface iwconfig ifconfig: configure a network interface ifconfig
How to install drivers for TL-WN725N v2 USB wireless adapter on Fedora 19
Posted onI had a TP-Link TL-WN725N v2 USB wireless adapter. But it seems the kernels in Fedora 19 have not yet included drivers for it. How to install drivers for TL-WN725N v2 on Fedora 19? The driver is under development. You can find the source here and in the drivers/staging in the Linux kernel. If you
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Enable debugging with cmake
Posted onHow to enable debugging with cmake? If we use cmake to build the project, we may want to enabling the debuging mode that cmake invoke gcc with the -g so that we can debug the compiled program with gdb. This can be enabled by adding the CMAKE_BUILD_TYPE parameter to cmake: cmake -DCMAKE_BUILD_TYPE=Debug . Then the
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How To Debug Linux Kernel With Less Efforts
Posted onIntroduction In general, if we want to debug Linux Kernel, there are lots of tools such as Linux Perf, Kprobe, BCC, Ktap, etc, and we can also write kernel modules, proc subsystems or system calls for some specific debugging aims. However, if we have to instrument kernel to achieve our goals, usually we would not
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x-data-plane feature in QEMU/KVM
Posted onAbstract In systems, sometimes, we use one global lock to keep synchronization among different threads. This principle also happens in QEMU/KVM (http://wiki.qemu.org/Main_Page) system. However, this may cause lock contention problem. The performance/scalability of whole system will be decreased. In order to solve this problem in QEMU/KVM, x-data-plane feature is designed/implemented, which the high-level idea is
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Three Methods of Executing Commands on Many Nodes in Parallel via SSH on Linux
Posted onIt is common to execute commands on many nodes/hosts via SSH for managing a cluster of Linux servers. On Linux, there are many choices for this task. Generally, to run commands on many nodes, there are two modes: serial mode and parallel mode. In serial mode, the command is executed on the node one by
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Notes for Beginners of Software Development on Linux
Posted onLinux is a great platform for software development targeting servers or backends. In general, working on Linux is very productive. The problem that beginners on Linux face is the the learning curve is steep at the beginning. But believe me, after you get through the initial green steep learning step as in the figure below
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Hadoop Installation Tutorial (Hadoop 2.x)
Posted onHadoop 2 or YARN is the new version of Hadoop. It adds the yarn resource manager in addition to the HDFS and MapReduce components. Hadoop MapReduce is a programming model and software framework for writing applications, which is an open-source variant of MapReduce designed and implemented by Google initially for processing and generating large data
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