Varieties of Kernel-Mode Dump Files
There are four setting for kernel-mode crash dump files:
The difference between these dump files is one of size. The Complete Memory Dump is the largest and contains the most information, the Kernel Memory Dump is somewhat smaller, and the Small Memory Dump is only 64 KB in size.
If you select Automatic Memory Dump, the dump file is the same as a Kernel Memory Dump, but Windows has more flexibility in setting the size of the system paging file.
The advantage to the larger files is that, since they contain more information, they are more likely to help you find the cause of the crash.
The advantage of the smaller files is that they are smaller and written more quickly. Speed is often valuable; if you are running a server, you may want the server to reboot as quickly as possible after a crash, and the reboot will not take place until the dump file has been written.
After a Complete Memory Dump or Kernel Memory Dump has been created, it is possible to create a Small Memory Dump file from the larger dump file. See the .dump (Create Dump File) command for details.