Enter the sync command at the ok prompt to force any information on its way to the hard
disk to be written out immediately. This command is useful if the operating system fails or
is interrupted before preserving all data.

The sync command returns control to the operating system and performs the data-saving
operations. After the disk data is synchronized, the operating system begins to save a core
image of itself. If you do not need this core dump, you can interrupt the operation by
pressing Stop+A.