Crashkernel feature uses up a useful amount of memory which is needed by the system itself. Therefore it is best to disable this feature to save up more memory for the System in general. Here is an easy procedure to Disable crashkernel in CentOS.
The most effective method of clearing up disk space via the inbuilt resources in CentOS. This Tutorial will show you how to free up space in your CentOS machine Safely and effectively without loosing vital files.