What are the most common causes for the collapsing of the website?

[Savannah87]

There are many kinds of factors may cause Web site does not work, which makes a systematic inspection of all the problem has become very difficult. The following analysis will focus on the Web site led to the collapse of summing up the most common problems. If you can solve these conventional problems, it will also have the ability to deal with the emergence of some unexpected situations. Hence I want to know the most common causes for the collapsing of the website

[Techno01]

With C or C + + written programs, such as Web server API modules, it may lead to the collapse of the system as long as an indirect reference pointer (ie, access point to the memory) in an error, it will cause the operating system to terminate all programs. In addition, the use of a poor C-pointer Java analog (analog) will visit an empty object reference. Java in the null reference do not usually lead to immediate withdrawal JVM, but the premise that programmers can use exception handling to properly handle the error. In this regard, Java without much concern, but the use of Java on the reliability of the additional measure of performance would have some negative effects.

[Trio]

C / C + + programs may also yield a pointer to another problem: the loss of the already allocated memory references. When the memory is being allocated in the subroutine, it is usually this problem occurs, the result is a program returns from the subroutine will not release memory. In this way, the reference to allocated memory will be lost, as long as the operating system is still running, then the process would have been using that memory. The result is that takes up more memory once the procedure will reduce system performance, until the machine completely stopped working, will completely empty the memory.

[deveritt]

Java itself has no pointers, but in general, compared with the C programs, Java programs use memory, the situation was even worse. In Java, objects are frequently created, but until all references to the object disappears, the garbage collector will release memory. Even running the garbage collection process, the memory will only be returned to the virtual machine VM, rather than be returned to the operating system. The result is: Java programs to run out to them all the heap, and never released. Because you want to save time (Just In Time, JIT) compiler generated code, Java programs can sometimes inflated the size of the largest of the giant heap several times.

[Techguru01]

If you have a Web server or other key processes assigned a file descriptor, but it needs more file descriptors, then the server or the process will be suspended or error, until the received file descriptor until the required . File descriptor is used to keep open the file and open socket track record, open the file and open socket is a Web server is a key component of its mandate is to copy the file to a network connection. By default, most of the shell there are 64 descriptors, which means that each process can be started from the shell at the same time to open 64 files and network connections. Most of the shell has a built-in ulimit command to increase the number of file descriptors.