|Anatomy of a Linux hypervisor
One of the most important modern innovations of Linux is its transformation into a hypervisor (or, an operating system for other operating systems). A number of hypervisor solutions have appeared that use Linux as the core. This article explores the ideas behind the hypervisor and two particular hypervisors that use Linux as the platform (KVM and Lguest).
|Articles||31 May 2009|
|Anatomy of Linux synchronization methods
In your Linux education, you may have learned about concurrency, critical sections, and locking, but how do you use these concepts within the kernel? This article reviews the locking mechanisms available within the 2.6 kernel, including atomic operators, spinlocks, reader/writer locks, and kernel semaphores. It also explores where each mechanism is most applicable for building safe and efficient kernel code.
|Articles||31 Oct 2007|
|Anatomy of the Linux kernel
The Linux kernel is the core of a large and complex operating system, and while it's huge, it is well organized in terms of subsystems and layers. In this article, you explore the general structure of the Linux kernel and get to know its major subsystems and core interfaces. Where possible, you get links to other IBM articles to help you dig deeper.
|Articles||06 Jun 2007|
|Anatomy of Linux Kernel Shared Memory
Linux as a hypervisor includes a number of innovations, and one of the more interesting changes in the 2.6.32 kernel is Kernel Shared Memory (KSM). KSM allows the hypervisor to increase the number of concurrent virtual machines by consolidating identical memory pages. Explore the ideas behind KSM (such as storage de-duplication), its implementation, and how you manage it.
|Articles||07 Apr 2010|
|Anatomy of Linux dynamic libraries
Dynamically linked shared libraries are an important aspect of GNU/Linux. They allow executables to dynamically access external functionality at run time and thereby reduce their overall memory footprint (by bringing functionality in when it's needed). This article investigates the process of creating and using dynamic libraries, provides details on the various tools for exploring them, and explores how these libraries work under the hood.
|Articles||20 Aug 2008|
|Anatomy of Security-Enhanced Linux (SELinux)
Linux has been described as one of the most secure operating systems available, but the National Security Agency (NSA) has taken Linux to the next level with the introduction of Security-Enhanced Linux (SELinux). SELinux takes the existing GNU/Linux operating system and extends it with kernel and user-space modifications to make it bullet-proof. If you're running a 2.6 kernel today, you might be surprised to know that you're using SELinux right now! This article explores the ideas behind SELinux and how it's implemented.
|Articles||17 May 2012|
|Anatomy of Linux flash file systems
You've probably heard of Journaling Flash File System (JFFS) and Yet Another Flash File System (YAFFS), but do you know what it means to have a file system that assumes an underlying flash device? This article introduces you to flash file systems for Linux, and explores how they care for their underlying consumable devices (flash parts) through wear leveling, and identifies the various flash file systems available along with their fundamental designs.
|Articles||20 May 2008|
|Anatomy of ext4
The fourth extended file system, or ext4, is the next generation of journaling file systems, retaining backward compatibility with the previous file system, ext3. Although ext4 is not currently the standard, it will be the next default file system for most Linux distributions. Get to know ext4, and discover why it will be your new favorite file system.
|Articles||17 Feb 2009|
|Anatomy of the Linux virtual file system switch
Linux is the very definition of flexibility and extensibility. Take the virtual file system switch (VFS). You can create file systems on a variety of devices, from traditional disk, USB flash drives, memory, and other storage devices. You can even embed a file system within the context of another file system. Discover what makes the VFS so powerful, and learn its major interfaces and processes.
|Articles||31 Aug 2009|
|Anatomy of the libvirt virtualization library
The libvirt library is a Linux API over the virtualization capabilities of Linux that supports a variety of hypervisors, including Xen and KVM, as well as QEMU and some virtualization products for other operating systems. This article explores libvirt, its use, and its architecture.
|Articles||05 Jan 2010|
|Anatomy of real-time Linux architectures
It's not that Linux isn't fast or efficient, but in some cases fast just isn't good enough. What's needed instead is the ability to deterministically meet scheduling deadlines with specific tolerances. Discover the various real-time Linux alternatives and how they achieve real time -- from the early architectures that mimic virtualization solutions to the options available today in the standard 2.6 kernel.
|Articles||15 Apr 2008|
|Anatomy of the Linux file system
When it comes to file systems, Linux is the Swiss Army knife of operating systems. Linux supports a large number of file systems, from journaling to clustering to cryptographic. Linux is a wonderful platform for using standard and more exotic file systems and also for developing file systems. This article explores the virtual file system (VFS) -- sometimes called the virtual filesystem switch -- in the Linux kernel and then reviews some of the major structures that tie file systems together.
|Articles||30 Oct 2007|
|Anatomy of Linux process management
The creation and management of user-space processes in Linux have many principles in common with UNIX but also include several unique optimizations specific to Linux. Here, review the life cycle of Linux processes and explore the kernel internals for user process creation, memory management, scheduling, and death.
|Articles||20 Dec 2008|
|Anatomy of Linux journaling file systems
In recent history, journaling file systems were viewed as an oddity and thought of primarily in terms of research. But today, a journaling file system (ext3) is the default in Linux. Discover the ideas behind journaling file systems, and learn how they provide better integrity in the face of a power failure or system crash. Learn about the various journaling file systems in use today, and peek into the next generation of journaling file systems.
|Articles||04 Jun 2008|