Re-order log statements to be correct for segment and top level warming.
Change default numeric precision_step

Change the default numeric precision_step to 16 for 64-bit types,
8 for 32-bit and 16-bit types. Disable precision_step for the 8-bit
byte type.

Closes #5905
Change default recovery throttling to 50MB / sec

The current setting of 20MB/sec seems to be too conservative given
the capabilities of modern hardware / network throughput.
A 50MB default should provide better out of the box performance.