Core Dump

Last Updated: October 25, 2012

Definition - What does Core Dump mean?

A core dump is a file of a computer’s documented memory of when a program or computer crashed. The file consists of the recorded status of the working memory at an explicit time, usually close to when the system crashed or when the program ended atypically.

Aside from the entire system memory or just part of the program that aborted, a core dump file may include additional information such as:

The processor's state
The processor register's contents
Memory management information
The program's counter and stack pointer
Operating system and processor information and flags

Core dump may also be known as memory dump, storage dump or dump.

Techopedia explains Core Dump

Programmers often use a core dump to examine the problem with the use of a debugger. A core dump can include all the system memory or a part of the program that failed. There are several reasons why a computer or program can crash:

Corrupted data
A severe user error
Virus-infected files
Problems accessing data files
An outdated operating system
A segmentation fault or bus error
A poorly ventilated or dusty computer tower
A system-detected fault in the software or hardware
Computer overheating caused by a faulty heat sink or fan

Generally, a core dump file includes the random access memory (RAM) contents of a certain process or part of an address space of the process and values of processor registers. The core dump files can be used to analyze the cause of the dump, viewed as text or printed.

Because a contemporary OS process address space may share breaks and pages with other files and processes, a more intricate image is used. In Unix-like systems, core dumps typically use the standard executable image format:

Mach-O in Mac OS X
a.out in older versions of Unix
Executable and linkable format (ELF) in modern Linux, Solaris, Unix System V and Berkeley software distribution (BSD) schemes

Originally, a core dump transferred the contents of memory precisely in order to record the state of the computer. The core dumps were actual printouts of around a hundred pages or more that consisted of octal or hexadecimal numbers. The pages were studied by programmers to research the cause of the crash or abnormally terminated program. Eventually, the introduction of debuggers eliminated the need for massive stacks of printouts.