Linux

Linux's introduction of large page memory has a good effect on reducing the failure of TLB, especially for memory-intensive programs, such as database usage. The innodb Engine supports large page memory. For more information, see

1. Download the installation file from http://www.open.collab.net/downloads/subversion.html. 2. Create a directory to save the code. Run the following command to start the terminal: svnadmin create/Users/ckwang17/svn_root. I created a code library

  In the vcpu overcommit environment, the 32-bit and 64-bit clock drift of rhel54 are different. 32bit system time slows down. This is reasonable, but 64bit system time gets faster. At first glance, it seems unreasonable and there is no reason to

  Start mysql   # Cd/usr/local/mysql/support-files/ #./Mysql. server start   Start memcached   Cd/usr/local/memcached/bin/ ./Memcached-d-m 256-u root-l 10.0.20.6-p000011-c 5000-P/usr/local/memcached/memcached1.pid     Startup options:  

  I. Static deployment   1. Directly copy the web project file to the webapps directory. The Webapps directory of Tomcat is the default application directory of Tomcat. When the server starts, all applications under this directory will be loaded.

  After using the Linux System of cen tos 5.5, I always like to study some things in Linux. Recently, this library has not exploded. So I also downloaded some databases. However, I like double insurance, and then back up data on my CentOS. I use

    1. List all software updates Command: yum check-update   2. Install all Update Software Command: yum update   3. Only install the specified Software Command: yum install   4. Update only the specified Software Command: yum update   5. list all

  1. garbled characters on the Character interface: by default, the character interface does not display Chinese characters and is full of diamond symbols, which greatly limits the use of Chinese users. The solution is as follows: First install

Linux memory management is based on the basic paging mechanism. Some parts of RAM in the linux Kernel will be permanently allocated to the kernel and used to store kernel code and static kernel data structures. The rest of RAM is called dynamic

Vsftpd startup error: vsftpd: 500 OOPS: bad bool value in config file for: anonymous_enable Solution: vi/etc/vsftpd. conf: do not have spaces in the values of each line. Otherwise, an error will occur during startup. For example, if I add spaces

Two main features of linux memory management are process virtual memory and kernel memory allocation. First, let's talk about the virtual memory of processes. linux uses a three-level page table structure, which consists of the page Directory, page

Basic Idea: Enable IP Forwarding and set iptables rules. 2. 1. Enable IP ForwardingTwo methods,Temporary: echo "1">/proc/sys/net/ipv4/ip_forwardFixed: Modify/etc/sysctl. conf to cancel the comments of this line:Net. ipv4.ip _ forward = 1Then make it

If you are using svn and want to switch to git and do not want to discard the existing svn code library, you can select git-svn. Let's talk about my experience from svn to git.  StartInstall the latest version of git. git 1.5.3 and later support git-

Nginx command optimization (configuration file)Worker_processes 8; number of nginx processes. It is recommended to specify the number of CPUs, which is generally a multiple of them. Worker_cpu_affinity 00000001 00000010 00000100 00001000 00010000 001

1. Install Sun's jdk1.6 and the JAVA_HOME environment variable has been directed to the jdk installation directory. (For details, refer to manual installation of SUN's jdk1.6 under Ubuntu10.4 [finishing])2. Download the stable version of hadoop

My laptop is equipped with Win7 and Ubuntu10.4LTS dual systems. With the upgrade of the Linux kernel, there will be more and more grub boot items when starting up. It is very troublesome to choose. Enter the following command, you can delete

1. Installation: apt-get install vnc4server 2. Change the password: vncpasswd 3. Start: vncserver: 1 4. The installation is complete. However, if you connect to bt5 on a windows machine (the connection method is ip: 1), there will be an interface

Function of the test command: check files and compare values.  1. judgment Expression If test (expression true) If test! (Expression is false) Test expression 1-Expression 2: both expressions are true. Test expression 1-oExpression 2: either of the

1. Write a java class/jsp Runtime run = Runtime. getRuntime (); Long max = run. maxMemory ()/1024/1024; // maximum memory Long total = run. totalMemory ()/1024/1024; // allocated memoryLong free = run. freeMemory ()/1024/1024; // available space If (

Hey hey, it's a small problem, that is, it's a headache to save the screen brightness, and the Bluetooth is always started on and off for some machines with the same Bluetooth and wireless switch... it makes Tom uncomfortable... however, this