MySQL 5.7 Release Notes
Given a Performance Schema latency or wait time in
picoseconds, converts it to human-readable format and returns
a string consisting of a value and a units indicator.
Depending on the size of the value, the units part is
ps
(picoseconds), ns
(nanoseconds), us
(microseconds),
ms
(milliseconds), s
(seconds), m
(minutes),
h
(hours), d
(days), or
w
(weeks).
mysql> SELECT sys.format_time(3501), sys.format_time(188732396662000);
+-----------------------+----------------------------------+
| sys.format_time(3501) | sys.format_time(188732396662000) |
+-----------------------+----------------------------------+
| 3.50 ns | 3.15 m |
+-----------------------+----------------------------------+