The final (optional) component of a query allows the user to
specify a specific time window of interest. Any time
specification will result in values being returned for all
matching timeseries only for the time window specified.
The specification is ``square'' bracket ([]) enclosed, and
consists of one or more comma-separated components. Each
component specifies some aspect related to time, taking the
general form: keyword: value, such as:
samples:10
Sample count
The number of samples to return, specified via either the samples
or (equivalent) count keyword. The value provided must be a
positive integer. If no end time is explicitly set (see ``Time
window'' later) then the most recent samples will be returned.
Sample interval
An interval between successive samples can be requested using the
interval or (equivalent) delta keyword. The value provided
should be either a numeric or string value that will be parsed by
pmParseInterval(3), such as 5 (seconds) or 2min (minutes).
Time window
Start and end times, and alignments, affecting the returned
values. The keywords match the parameters to the
pmParseTimeWindow(3) function which will be used to parse them,
and are: start or (equivalent) begin, finish or (equivalent) end,
align and offset.
Time zones
The resulting timestamps can be returned having been evaluated
for a specific timezone, using the timezone or hostzone keywords.
The value associated with timezone will be interpreted by
pmNewZone(3). A true or false value should be associated with
hostzone, and when set to true this has the same effect as
described by pmNewContextZone(3).
