Hardware Clock Sync Failure
A normal day. I booted the office computer. The computer hung for about a minute and a half when the system clock is synced to the hardware clock.
A few more reboots with the same result.
hwclock --debug and rebooted. The output spew included
Waiting for clock tick and
I stared for several moments.
I fetched a new CMOS battery.
I seemed to recall changing the battery not long ago. Some digging revealed less than a year ago.
Bad battery? Bad luck?