 Like the other BSD kernels ( and those of most modern operating systems ) , DragonFly employs a built @-@ in kernel debugger to help the developers find kernel bugs . Furthermore , as of October 2004 , a debug kernel , which makes bug reports more useful for tracking down kernel @-@ related problems , is installed by default , at the expense of a relatively small quantity of disk space . When a new kernel is installed , the backup copy of the previous kernel and its modules are stripped of their debugging symbols to further minimize disk space usage . 
