[sheepdog] [PATCH v3 3/7] sheep: teach journal file to handle epoch and config write

[Liu Yuan]

On 04/05/2013 05:06 PM, Hitoshi Mitake wrote:
> Simply causing panic() makes the patchset smaller. I feel the current
> behavior is too dangerous because users have no way to know disabling
> of journals until they read the log messages.

Actually, from the feedback of our production system, users are more
sensitive to panic. Panic means VM resource is suddenly unusable and a
big possibility to break the VM's FS. This will always be last resort to
consider. Sheepdog plays a more vital role than hyper visor in cloud
computing environment because it deals with data directly. Disable
journaling is not as dangerous than panic out. Or what exactly danger
you think of about disabling journaling?

Thanks,
Yuan