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Io Uring
io_uring is a Linux kernel system call interface for storage device asynchronous I/O operations addressing performance issues with similar interfaces provided by functions like / or / etc. for operations on data accessed by file descriptors. Development is ongoing, worked on primarily by Jens Axboe at Meta. Interface It works by creating two circular buffers, called "queue rings", to track the submission and completion of I/O requests, respectively. For storage devices, these are called the submission queue (SQ) and completion queue (CQ). Keeping these buffers shared between the kernel and application helps to boost the I/O performance by eliminating the need to issue extra and expensive system calls to copy these buffers between the two. According to the io_uring design paper, the SQ buffer is writable only by consumer applications, and the CQ buffer is writable only by the kernel. eBPF can be combined with io_uring. History The Linux kernel has supported asynchronous I/O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asynchronous I/O
In computer science, asynchronous I/O (also non-sequential I/O) is a form of input/output processing that permits other processing to continue before the I/O operation has finished. A name used for asynchronous I/O in the Windows API is '' overlapped I/O''. Input and output (I/O) operations on a computer can be extremely slow compared to the processing of data. An I/O device can incorporate mechanical devices that must physically move, such as a hard drive seeking a track to read or write; this is often orders of magnitude slower than the switching of electric current. For example, during a disk operation that takes ten milliseconds to perform, a processor that is clocked at one gigahertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), often described as being equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose formal expression in terms of SI base un ... could have performed ten million instruct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jens Axboe
Jens Axboe (born circa 1976) is a Linux kernel hacker. Work Axboe is the current Linux kernel maintainer of the block layer and other block devices, along with contributing the CFQ I/O scheduler, Noop scheduler, Deadline scheduler, io_uring, and the splice I/O architecture. Jens is also the author of the blktrace utility and kernel parts, which provides a way to trace every block I/O activity in the Linux kernel. blktrace exists in 2.6.17 and later Linux kernels. To facilitate his block layer work in the Linux kernel, Axboe created the flexible I/O tester (fio) benchmarking and workload simulation tool. fio is able to simulate various types of I/O loads, such as synchronous, asynchronous, mmap, etc., as well as specifying the number of threads or processes, read vs. write mix, and various other parameters. fio was used to set the record in December 2012 for the highest number of I/Os-per-second (IOPS) in a single system. In May 2010 Axboe joined Fusion-io after leaving Or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux Kernel
The Linux kernel is a Free and open-source software, free and open source Unix-like kernel (operating system), kernel that is used in many computer systems worldwide. The kernel was created by Linus Torvalds in 1991 and was soon adopted as the kernel for the GNU operating system (OS) which was created to be a free software, free replacement for Unix. Since the late 1990s, it has been included in many Linux distributions, operating system distributions, many of which are called Linux. One such Linux kernel operating system is Android (operating system), Android which is used in many mobile and embedded devices. Most of the kernel code is written in C (programming language), C as supported by the GNU compiler collection (GCC) which has extensions beyond standard C. The code also contains assembly language, assembly code for architecture-specific logic such as optimizing memory use and task execution. The kernel has a Modular programming, modular design such that modules can be inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Userspace
A modern computer operating system usually uses virtual memory to provide separate address spaces or regions of a single address space, called user space and kernel space. This separation primarily provides memory protection and hardware protection from malicious or errant software behaviour. Kernel space is strictly reserved for running a privileged operating system kernel, kernel extensions, and most device drivers. In contrast, user space is the memory area where application software and some drivers execute, typically with one address space per process. Overview The term user space (or userland) refers to all code that runs outside the operating system's kernel. User space usually refers to the various programs and libraries that the operating system uses to interact with the kernel: software that performs input/output, manipulates file system objects, application software, etc. Each user space process usually runs in its own virtual memory space, and, unless explici ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interfaces Of The Linux Kernel
Interface or interfacing may refer to: Academic journals * ''Interface'' (journal), by the Electrochemical Society * '' Interface, Journal of Applied Linguistics'', now merged with ''ITL International Journal of Applied Linguistics'' * '' Interface: A Journal for and About Social Movements'' * ''Interface'', shortened name for the ''Journal of the Royal Society Interface'', covering the interface between life sciences and physical sciences * ''Interfaces'' (journal), now ''INFORMS Journal on Applied Analytics'' Arts and entertainment * ''Interface'' (album), by Dominion, 1996 * Interface (band), an American music group * ''Interface'' (film), a 1984 American film * ''Interface'' (novel), by Stephen Bury (a pseudonym), 1994 * "Interface" (''Star Trek: The Next Generation''), an episode of the TV series * '' Interface series'', a science fiction horror story in short installments on Reddit Science and technology * Interface (computing), a shared boundary between system comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seccomp
seccomp (short for secure computing) is a computer security facility in the Linux kernel. seccomp allows a process to make a one-way transition into a "secure" state where it cannot make any system calls except exit(), sigreturn(), read() and write() to already-open file descriptors. Should it attempt any other system calls, the kernel will either just log the event or terminate the process with SIGKILL or SIGSYS. In this sense, it does not virtualize the system's resources but isolates the process from them entirely. seccomp mode is enabled via the system call using the PR_SET_SECCOMP argument, or (since Linux kernel 3.17) via the system call. seccomp mode used to be enabled by writing to a file, /proc/self/seccomp, but this method was removed in favor of prctl(). In some kernel versions, seccomp disables the RDTSC x86 instruction, which returns the number of elapsed processor cycles since power-on, used for high-precision timing. seccomp-bpf is an extension to seccomp tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Docker (software)
Docker is a set of platform as a service (PaaS) products that use OS-level virtualization to deliver software in packages called ''containers''. The service has both free and premium tiers. The software that hosts the containers is called Docker Engine. It was first released in 2013 and is developed by Docker, Inc. Docker is a tool that is used to automate the deployment of applications in lightweight containers so that applications can work efficiently in different environments in isolation. Background Containers are isolated from one another and bundle their own software, libraries and configuration files; they can communicate with each other through well-defined channels. Because all of the containers share the services of a single operating system kernel, they use fewer resources than virtual machines. Operation Docker can package an application and its dependencies in a virtual container that can run on any Linux, Windows, or macOS computer. This enables the appli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ChromeOS
ChromeOS, sometimes styled as chromeOS and formerly styled as Chrome OS, is an operating system designed and developed by Google. It is derived from the open-source operating system and uses the Google Chrome web browser as its principal user interface. Google announced the project in July 2009, initially describing it as an operating system where applications and user data would reside in the cloud. ChromeOS was used primarily to run web applications. ChromeOS supports progressive web applications, Android apps from Google Play and Linux applications. History In 2006, Jeff Nelson, a Google employee, created the concept of what would become ChromeOS, initially codenamed "Google OS" as a Linux distribution focused on speed. Early Google OS versions used Firefox as Chrome had not been released, though it switched to Chrome sometime in 2007 due to internal betas being passed around Google. To ascertain marketing requirements, developers relied on informal metrics, includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Android (operating System)
Android is an operating system based on a modified version of the Linux kernel and other open-source software, open-source software, designed primarily for touchscreen-based mobile devices such as smartphones and tablet computer, tablets. Android has historically been developed by a consortium of developers known as the Open Handset Alliance, but its most widely used version is primarily developed by Google. First released in 2008, Android is the world's Usage share of operating systems, most widely used operating system; the latest version, released on June 10, 2025, is Android 16. At its core, the operating system is known as the Android Open Source Project (AOSP) and is free and open-source software (FOSS) primarily licensed under the Apache License. However, most devices run the proprietary software, proprietary Android version developed by Google, which ships with additional proprietary closed-source software pre-installed, most notably Google Mobile Services (GMS), which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bug Bounty Program
A bug bounty program is a deal offered by many websites, organizations, and software developers by which individuals can receive recognition and compensation for reporting bugs, especially those pertaining to security vulnerabilities. If no financial reward is offered, it is called a vulnerability disclosure program. These programs, which can be considered a form of crowdsourced penetration testing, grant permission for unaffiliated individuals—called bug bounty hunters, white hats or ethical hackers—to find and report vulnerabilities. If the developers discover and patch bugs before the general public is aware of them, cyberattacks that might have exploited are no longer possible. Participants in bug bounty programs come from a variety of countries, and although a primary motivation is monetary reward, there are a variety of other motivations for participating. Hackers could earn much more money for selling undisclosed zero-day vulnerabilities to brokers, spyware co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exploit (computer Security)
An exploit is a method or piece of code that takes advantage of Vulnerability (computer security), vulnerabilities in software, Application software, applications, Computer network, networks, operating systems, or Computer hardware, hardware, typically for malicious purposes. The term "exploit" derives from the English verb "to exploit," meaning "to use something to one’s own advantage." Exploits are designed to identify flaws, bypass security measures, gain unauthorized access to systems, take control of systems, install malware, or data breach, steal sensitive data. While an exploit by itself may not be a malware, it serves as a vehicle for delivering malicious software by breaching security controls. Researchers estimate that malicious exploits cost the global economy over US$450 billion annually. In response to this threat, organizations are increasingly utilizing cyber threat intelligence to identify vulnerabilities and prevent hacks before they occur. Description Expl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux Security Modules
Linux Security Modules (LSM) is a framework allowing the Linux kernel to support, without bias, a variety of computer security models. LSM is licensed under the terms of the GNU General Public License and is a standard part of the Linux kernel since Linux 2.6. AppArmor, LoadPin, SELinux, Smack, TOMOYO, Yama, SafeSetID, Integrity Policy Enforcement (IPE), and Landlock are the currently approved security modules in the official kernel. Design LSM was designed in order to answer all the requirements for successfully implementing a mandatory access control module, while imposing the fewest possible changes to the Linux kernel. LSM avoids the approach of system call interposition used by Systrace because it doesn't scale to multiprocessor kernels and is subject to TOCTTOU (race) attacks. Instead, LSM inserts " hooks" (upcalls to the module) at every point in the kernel where a user-level system-call is about to result with an access to an important internal kernel-object ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
