used memory

The commands for performance monitoring analysis include the following:1, Vmstat2. Sar3, Iostat4. Top5. Free6, uptime7, Netstat8, PS9, Strace10, LsofCommand Description:The free command is the most common command for monitoring Linux memory

Processor internal registers, the fastest access, but the number of smallTCM: Tightly coupled memory (Cache, main memory)Secondary memory (Flash, SD, etc.)Cache is a small, but very fast-access memoryIt keeps a copy of the data in the most recently

During system maintenance, it may be necessary to review the CPU usage at any time, and to analyze the system condition according to the corresponding information. In CentOS, you can view CPU usage by using the top command. After running the top

What is a MySQL databaseTypically, a database is a collection of data, and a database can be a collection of files on a memory or a collection of some memory data.What we usually call MySQL database, SQL Server database and so on is actually a

During system maintenance, it may be necessary to review the CPU usage at any time, and to analyze the system condition according to the corresponding information. In CentOS, you can view CPU usage by using the top command. After running the top

PS command: View StaticThe process statistics informationP s : will show only the processes that are open in the current user session without any parameters 、P s aux : All process information will be displayed as a simple list Comments:U ser: The

System Detection Tool top command in LinuxThis article transferred from: https://www.cnblogs.com/zhoug2020/p/6336453.htmlFirst, describe the meanings of some of the fields in top:Virt:virtual Memory usage Virtual RAM1. The process "required" virtual

Linux provides us with some tools to view some of the status of the process, we can view the status of the process through top dynamic real-time information such as CPU, memory information, and so on, we can also use PS to statically view the

MySQL storage engine total results frozen want font: [Increase decrease] Type: Reproduced this article mainly introduces the MySQL storage engine summary, this article explains what is storage engine, MyISAM, InnoDB, memory, merge and other content,

01. Environment variable File description/etc/profile: This file sets the environment information for each user of the system, and when the user first logs on, the file is executed and the shell's settings are collected from the configuration file

Ceph deadlock failure under high IO On a high-performance PC server, ceph is used for VM image storage. In the case of stress testing, all virtual machines on the server cannot be accessed. Cause: 1. A website service is installed on the virtual

TCP sending series-manage the sending cache (2) (1) TCP sending Cache Management takes place at two layers: A single Socket and the entire TCP layer. The previous blog talked about sending Cache Management on a single Socket layer. Now let's take a

IntroductionThe garbage collection technology was not the first in the Java language, and the 1960 birth of the Lisp at MIT was the only language that really used memory dynamic allocation and garbage collection techniques. The three issues to

This article mainly introduces node-images, a middleware for processing images by nodejs, which is of great practical value, for more information about node-images, see the next article. It is very useful. Cross-platform image decoder (png/jpeg/gif)

Program --- C language details 17 (calculate the maximum value of time_t, strlen calculates the length, malloc allocates characters memory details, and switch's default details) Main Content: calculate the maximum value of time_t, strlen evaluate

Article Title: Free command details and release of linuxCache. Linux is a technology channel of the IT lab in China. Including desktop applications, Linux system management, kernel research, embedded systems, open source, and other basic categories.

0. Garbage Collection Algorithm OverviewTag Cleanup Algorithm | | ---marking time too long | | | | ---CMS: Split the tagging process with initial tags, concurrency tags, and re-tagging | | Excessive memory fragmentation after---garbage collection | |

If you have read the ziplist compressed list analysis I have analyzed, I think this is not a special problem. Ziplist compression lists and zipmap both use the dynamic byte allocation method to indicate the length. For example, the fixed byte

Memories of database optimization and Memacache distributed cache, memacache Cache     Horizontal database sharding1. Store database files on different disks to make full use of disk ioTable Partitioning1. Table databases can be

Original link Http://www.cnblogs.com/gw811/archive/2012/10/19/2730258.html#topJava garbage collectorOverview Speaking of garbage collection (garbage collection,gc), most people regard this technique as the companion product of the Java