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Performance Tuning: IO consumption analysis, performance tuning io consumption Performance Tuning-> how to analyze io consumption Reprinted please indicate the source: http://blog.csdn.net/supera_li/article/details/45225077For more information about the performance tuning series, see.Performance Optimization: Analysis of CPU consumptionPerformance Optimization:

1, event channel model. The event channel is the prototype of asynchronous IO.2, io mode, one IO call will go through two stages. First, wait for the data phase, the data from the network or disk read to the system kernel (kennel) Two, the data from the kernel copy into the process.Based on these two phases, the Linux system generates five network mode scenarios.

Java BASICS (12) IO input and output, java basics io Input and OutputI. IO Overview 1. IO concepts IO: I represents Input; O represents Output. In Java, IO is input and output based on a stream. AllSerializing data(SAVE) write to

Node. js uses the socket. io method, node. jssocket. io You can use socket. io to create a socket. io server. However, this server depends on a created http server. After the http server is running, use the listen method to append a socket. io server to the http server. Copy

Today, I summarize this point of Io flow, because when I used the IO stream, I knew only a few of the most commonly used IO classes, such as Fileinputstream,bufferedinputstream (buffer stream), etc. But I do not know where it is in the entire IO system, for the whole IO syst

When the program is IO, the IO is blocked if the data is not ready. When a process has multiple open files, such as a socket, then all files that are ready to be read and written will be affected by blocking and cannot be manipulated. Without threading, a single process cannot serve multiple file descriptors at the same time. Non-blocking IO can be used as a solu

JAVA 56th-IO stream (10) Object serialization and deserialization RandomAccessFile, io serialization Operation object ObjectInputStream and ObjectOutputStream The operated object must implement Serializable (Mark Interface) ObjectOutputStream writes the basic data types and graphics of Java objects to OutputStream. You can use ObjectInputStream to read (refactor) objects. Objects can be stored permanently

Java IO learning notes (4) print stream and io learning notes1. Only the output stream has a print stream: PrintWriter and PrintStream provide a heavy print for characters and bytes respectively. The Println method is used for output of multiple data types. The PrintWriter and PrintStream operations do not throw an exception. If the data is not printed, the system does not throw an exception. 2. System. out

One, I/O ports Port is the address of a register that can be accessed directly by the CPU in an interface circuit. Almost every peripheral is done by reading and writing registers on the device. The CPU sends commands to the registers in the interface circuit through these address ports, reading status and transmitting data. Peripheral registers, also known as "I/O ports", typically include three categories of control registers, state registers, and data registers, and the registers of a periph

J2SE quick advanced -- IO stream, j2se advanced io Concept of IO stream An IO stream is an abstraction that flows data from one place to another, just as a flow of water flows from one end of the pipeline to the other. In a program, all data is transmitted and saved as a stream. All the stream classes provided by JDK

Excerpted from http://blog.chinaunix.net/uid-26565142-id-3051729.html1, the file IO function , in Unix, has the following 5: Open,read,write,lseek,close. Known as IO without cache (unbuffered I/O). Without caching, each read,write is called by a system call in the kernel.2, standard IO library , described by ANSI C standard. The standard

I. I/O portA port is the address of a register in an interface circuit that can be accessed directly by the CPU. Almost every peripheral is made from a register on a read-write device. The CPU sends commands to the registers in the interface circuit through these addresses, namely ports, to read the status and transmit the data. Peripheral registers, also known as "I/O ports", typically include: control registers, status registers, and data registers, and the registers of a peripheral are usuall

Custom IO Async Basics:--all requests are based on the socket implementation, and a request is a socketSocket.setblocking (False) does not need to block, a request is over send another, will error, need to solve--io multiplexing [is a synchronous request]IO multiplexing has epoll, poll, select, knowing that epoll performance is better than others [Epoll find the

Five I/O modes-blocking (default IO mode), non-blocking (common language pipeline), I/O multiplexing (IO multiplexing scenario), signal I/O, asynchronous I/OFive I/O modes:"1" Blocking I/O (I/O operations under Linux are blocking I/O by default, that is, open and socket created I/O are blocked I/O)"2" non-blocking I/O (can be set to non-blocking I/O by using the O_nonblock parameter with FCNTL or open)"3" I

Asynchronous Io, APC, Io completion port, thread pool, and high-performance server (APC)Alertable Io provides a more effective asynchronous notification format. Readfileex/writefileex provides a callback function (APC process) when sending an IO request. After the IO request

Java-IO basic class memories and java-io basic memories For Java I/O, I have already learned this basic category in college, but I forgot about it. So I am going to write a blog, let's take a look at all these things and sort them out. First, use a picture on the Internet: Vertical streams are divided into byte streams and byte streams. Horizontal streams are divided into read and write streams. In this fig