`New-XbBatchBounds` - exponential dropoff

[petervandivier]

New-XbBatchBounds starts to really slow down around 20,000 batches or so. This is about 2 years worth of 1-hour spans. Tune if possible and warn if not.

From a spot-check:	batches	seconds	additional_time	rps
8,760	6.6		1,327.3
17,520	40.7	34.1	430.5
26,304	107.4	66.7	244.9
35,064	187.8	80.4	186.7
43,824	332.4	144.6	131.8
52,584	490.2	157.8	107.3
61,368	563.4	73.2	108.9
70,128	940.2	376.8	74.6

$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1971-01-01 00:00Z' -Step '01:00:00'
$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1972-01-01 00:00Z' -Step '01:00:00'
$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1973-01-01 00:00Z' -Step '01:00:00'
$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1974-01-01 00:00Z' -Step '01:00:00'
$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1975-01-01 00:00Z' -Step '01:00:00'
$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1976-01-01 00:00Z' -Step '01:00:00'
$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1977-01-01 00:00Z' -Step '01:00:00'
$batches = New-XbBatchBounds -Start '1970-01-01 00:00Z' -End '1978-01-01 00:00Z' -Step '01:00:00'
$batches.Count