HAMMER version 4 work in progress (NOT for production systems)

[Matthew Dillon]

    Here's an update on the version 4 WIP testing.

    I pulled the SATA cable on the drive a bunch of times and forced HAMMER
    to go into crash recovery and it seemed to do a good job.

    I will probably implement the actual REDO as version 5.  There's already
    plenty in version 4 related to the UNDO FIFO changes to support faster
    flushes and the later REDO to warrent its own version.

    However, I want to do another weeks worth of testing for version 4
    to be sure.  Version 4 is still WIP and is not yet ready for prime
    time.

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>