perf: run the gc before each run
The python garbage collector is a large source of performance troubles, we run
it right before the timed section to reduce the change for the gc to add noise
to the benchmark.
Some commands allow the user to specify a date, e.g.:
- backout, commit, import, tag: Specify the commit date.
- log, revert, update: Select revision(s) by date.
Many date formats are valid. Here are some examples:
- ``Wed Dec 6 13:18:29 2006`` (local timezone assumed)
- ``Dec 6 13:18 -0600`` (year assumed, time offset provided)
- ``Dec 6 13:18 UTC`` (UTC and GMT are aliases for +0000)
- ``Dec 6`` (midnight)
- ``13:18`` (today assumed)
- ``3:39`` (3:39AM assumed)
- ``3:39pm`` (15:39)
- ``2006-12-06 13:18:29`` (ISO 8601 format)
- ``2006-12-6 13:18``
- ``2006-12-6``
- ``12-6``
- ``12/6``
- ``12/6/6`` (Dec 6 2006)
- ``today`` (midnight)
- ``yesterday`` (midnight)
- ``now`` - right now
Lastly, there is Mercurial's internal format:
- ``1165411109 0`` (Wed Dec 6 13:18:29 2006 UTC)
This is the internal representation format for dates. The first number
is the number of seconds since the epoch (1970-01-01 00:00 UTC). The
second is the offset of the local timezone, in seconds west of UTC
(negative if the timezone is east of UTC).
The log command also accepts date ranges:
- ``<DATE`` - at or before a given date/time
- ``>DATE`` - on or after a given date/time
- ``DATE to DATE`` - a date range, inclusive
- ``-DAYS`` - within a given number of days from today