genunix: [ID 672855 kern.notice] syncing file systems...
What does "syncing file systems..." do?
At every boot, I see "syncing file systems..."
However, prior to an unknown error condition where the system will not come up from a hard boot, the previous reboot was missing this statement: "syncing file systems.."
What does this statement mean, and what is it's relevance when it is missing?

