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Mpstat
mpstat is a computer command-line software used in Unix-type operating systems to report (on the screen) processor-related statistics. It is used in computer monitoring in order to diagnose problems or to build statistics about a computer's CPU usage. Description The mpstat command writes to standard output activities for each available processor. The mpstat command can be used both on SMP and UP machines, but in the latter, only global average activities will be printed. Usage $ mpstat Interval is the time in seconds between printing out a line of statistics. Count is the number of lines of output you want. Note that the first line of output from mpstat (like iostat, vmstat, etc.) contains averages since system boot. The subsequent lines will show current values. Examples Different examples of output under different operating systems: under Linux kernel 4.14 on a two CPU machine: Linux 4.14.24.mptcp (hostname) 05/23/2018 _x86_64_ (2 CPU) 03:51:19 PM CPU ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iostat
iostat (''input/output statistics'') is a computer system monitor tool used to collect and show operating system computer data storage, storage input and output statistics. It is often used to identify performance issues with storage devices, including local Disk storage, disks, or remote disks accessed over network file systems such as Network File System, NFS. It can also be used to provide information about Computer terminal, terminal (TTY) input and output, and also includes some basic CPU information. Syntax and availability iostat -x displays output where each line (row) gives numerical data for one device. The first column lists the device name, and subsequent columns show various statistics for that device. Columns include the average service time (''svc_t'', which includes not only the time a request is in the service queue, but also the seek time and transfer time), the average busy percentage (''%b'', essentially the proportion of time that the device is in use), and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Top (software)
top is a task manager or system monitor program, found in many Unix-like operating systems, that displays information about CPU and memory utilization. Overview The program produces an ordered list of running processes selected by user-specified criteria, and updates it periodically. Default ordering is by CPU usage, and only the top CPU consumers are shown (hence the name). top shows how much processing power and memory are being used, as well as other information about the running processes. Some versions of top allow extensive customization of the display, such as choice of columns or sorting method. top is useful for system administrators, as it shows which users and processes are consuming the most system resources at any given time. Implementations There are several different versions of top. The traditional Unix version was written by William LeFebvre and originally copyrighted in 1984. It is hosted on SourceForge, and release 3.7 was announced in 2008. The Linux vers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer
A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic sets of operations known as Computer program, ''programs'', which enable computers to perform a wide range of tasks. The term computer system may refer to a nominally complete computer that includes the Computer hardware, hardware, operating system, software, and peripheral equipment needed and used for full operation; or to a group of computers that are linked and function together, such as a computer network or computer cluster. A broad range of Programmable logic controller, industrial and Consumer electronics, consumer products use computers as control systems, including simple special-purpose devices like microwave ovens and remote controls, and factory devices like industrial robots. Computers are at the core of general-purpose devices ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Software
Software consists of computer programs that instruct the Execution (computing), execution of a computer. Software also includes design documents and specifications. The history of software is closely tied to the development of digital computers in the mid-20th century. Early programs were written in the machine language specific to the hardware. The introduction of high-level programming languages in 1958 allowed for more human-readable instructions, making software development easier and more portable across different computer architectures. Software in a programming language is run through a compiler or Interpreter (computing), interpreter to execution (computing), execute on the architecture's hardware. Over time, software has become complex, owing to developments in Computer network, networking, operating systems, and databases. Software can generally be categorized into two main types: # operating systems, which manage hardware resources and provide services for applicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix
Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley ( BSD), Microsoft (Xenix), Sun Microsystems ( SunOS/ Solaris), HP/ HPE ( HP-UX), and IBM ( AIX). The early versions of Unix—which are retrospectively referred to as " Research Unix"—ran on computers such as the PDP-11 and VAX; Unix was commonly used on minicomputers and mainframes from the 1970s onwards. It distinguished itself from its predecessors as the first portable operating system: almost the entire operating system is written in the C programming language (in 1973), which allows U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operating System
An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for efficient use of the system and may also include accounting software for cost allocation of Scheduling (computing), processor time, mass storage, peripherals, and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computerfrom cellular phones and video game consoles to web servers and supercomputers. , Android (operating system), Android is the most popular operating system with a 46% market share, followed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Processing Unit
A central processing unit (CPU), also called a central processor, main processor, or just processor, is the primary Processor (computing), processor in a given computer. Its electronic circuitry executes Instruction (computing), instructions of a computer program, such as arithmetic, logic, controlling, and input/output (I/O) operations. This role contrasts with that of external components, such as main memory and I/O circuitry, and specialized coprocessors such as graphics processing units (GPUs). The form, CPU design, design, and implementation of CPUs have changed over time, but their fundamental operation remains almost unchanged. Principal components of a CPU include the arithmetic–logic unit (ALU) that performs arithmetic operation, arithmetic and Bitwise operation, logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that orchestrates the #Fetch, fetching (from memory), #Decode, decoding and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Monitoring
Computer and network surveillance is the monitoring of computer activity and data stored locally on a computer or data being transferred over computer networks such as the Internet. This monitoring is often carried out covertly and may be completed by governments, corporations, criminal organizations, or individuals. It may or may not be legal and may or may not require authorization from a court or other independent government agencies. Computer and network surveillance programs are widespread today, and almost all Internet traffic can be monitored. Surveillance allows governments and other agencies to maintain social control, recognize and monitor threats or any suspicious or abnormal activity, and prevent and investigate criminal activities. With the advent of programs such as the Total Information Awareness program, technologies such as high-speed surveillance computers and biometrics software, and laws such as the Communications Assistance For Law Enforcement Act, governme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CPU Usage
CPU time (or process time) is the amount of time that a central processing unit (CPU) was used for processing instructions of a computer program or operating system. CPU time is measured in clock ticks or seconds. Sometimes it is useful to convert CPU time into a percentage of the CPU capacity, giving the CPU usage. Measuring CPU time for two functionally identical programs that process identical inputs can indicate which program is faster, but it is a common misunderstanding that CPU time can be used to compare ''algorithms''. Comparing programs by their CPU time compares specific ''implementations'' of algorithms. (It is possible to have both efficient and inefficient implementations of the same algorithm.) Algorithms are more commonly compared using measures of time complexity and space complexity. Typically, the CPU time used by a program is measured by the operating system, which schedules all of the work of the CPU. Modern multitasking operating systems run hundred ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symmetric Multiprocessing
Symmetric multiprocessing or shared-memory multiprocessing (SMP) involves a multiprocessor computer hardware and software architecture where two or more identical processors are connected to a single, shared main memory, have full access to all input and output devices, and are controlled by a single operating system instance that treats all processors equally, reserving none for special purposes. Most multiprocessor systems today use an SMP architecture. In the case of multi-core processors, the SMP architecture applies to the cores, treating them as separate processors. Professor John D. Kubiatowicz considers traditionally SMP systems to contain processors without caches. Culler and Pal-Singh in their 1998 book "Parallel Computer Architecture: A Hardware/Software Approach" mention: "The term SMP is widely used but causes a bit of confusion. ..The more precise description of what is intended by SMP is a shared memory multiprocessor where the cost of accessing a memory location ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vmstat
vmstat (''virtual memory statistics'') is a computer system monitoring tool that collects and displays summary information about operating system memory, processes, interrupts, paging and block I/O. Users of vmstat can specify a sampling interval which permits observing system activity in near-real time. The vmstat tool is available on most Unix and Unix-like operating systems, such as FreeBSD, Linux or Solaris. Syntax The syntax and output of vmstat often differs slightly between different operating systems. # vmstat 2 6 procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 0 0 2536 21496 185684 1353000 0 0 0 14 1 2 0 0 100 0 0 0 2536 21496 185684 1353000 0 0 0 28 1030 145 0 0 100 0 0 0 2536 21496 185684 1353000 0 0 0 0 1026 132 0 0 100 0 0 0 2536 21520 185684 1353000 0 0 0 0 103 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nmon
nmon (''Nigel's Monitor'') is a computer performance system monitor tool for the AIX and Linux operating systems. The nmon tool has two modes a) displays the performance stats on-screen in a condensed format or b) the same stats are saved to a comma-separated values (CSV) data file for later graphing and analysis to aid the understanding of computer resource use, tuning options and bottlenecks. nmon for Linux is open source and available under GNU General Public License while the nmon for AIX is a proprietary software integrated into AIX. Description nmon collects the following operating system statistics: * CPU and CPU threads Utilisation * CPU frequency for servers or virtual machines that can alter their clock rate * GPU stats including utilisation, MHz and temperatures * Physical and Virtual Memory use * Disk read & write and transfers plus service time and wait times * Disk Groups - decided by the user * Swap and Paging * Network read & write and transfers * Local File-syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
