What to do if GDB throws error of truncated core-dump file

Introduction

Laymen explanation

Process coredump contains info which is used to debug the crash. This data size can be bigger than allowed core file size limit. In such case, data is truncated and so, coredump file is incomplete for debugger (gdb) to process.

Technical explanation

Coredump contains process memory snapshot. Its actual size varies based on memory allocation by process. If lots of memory is allocated, then core-file size requirement can exceed limit enforced by OS. So, truncated core-dump will be generated.

How to get full core-dump

In linux, system limit for coredump can be configured as unlimited. In the C shell, you can set the maximum allowable core file size using the limit command (see the limit(1) man page). In the Bourne shell and Korn shell, use the ulimit command (see the limit(1) man page). After change, example output will be as below(Ref: core file size).

Method to enable core-dump and set dump directory path

Below command will enable core-dump generation to /var/crash.

Enable unlimited core-dump generated at /var/crash

ulimit -c unlimited

echo "/var/crash/core.%e.%p.%s" > /proc/sys/kernel/core_pattern

Reference

http://docs.oracle.com/cd/E19205-01/819-5257/blabs/index.html

http://unix.stackexchange.com/questions/155389/can-anything-useful-be-done-with-a-truncated-core

https://kb-stage.netapp.com/support/index?page=content&id=1014018&cat=STORAGEGRID&actp=LIST

https://sigquit.wordpress.com/2009/03/13/the-core-pattern/