DOC: Perf notes

[jbrockmendel]

• closes #xxxx
• tests added / passed
• Ensure all linting tests pass, see here for how to run them
• whatsnew entry

[jreback]

OT

Falsifying example: test_range_difference(
    start1=1, stop1=-3, step1=-1, start2=0, stop2=-3, step2=-2,
)
Traceback (most recent call last):
  File "/home/runner/work/pandas/pandas/pandas/tests/indexes/ranges/test_setops.py", line 472, in test_range_difference
    tm.assert_index_equal(result, alt, exact="equiv")
  File "/home/runner/work/pandas/pandas/pandas/_testing/asserters.py", line 408, in assert_index_equal
    raise_assert_detail(obj, msg, left, right)
  File "/home/runner/work/pandas/pandas/pandas/_testing/asserters.py", line 679, in raise_assert_detail
    raise AssertionError(msg)
AssertionError: Index are different

Index values are different (100.0 %)
[left]:  RangeIndex(start=0, stop=-3, step=-2)
[right]: Int64Index([1, -1], dtype='int64')


You can reproduce this example by temporarily adding @reproduce_failure('6.23.3', b'AAABAQMBAQAAAQMBAg==') as a decorator on your test case
Falsifying example: test_range_difference(
    start1=1, stop1=-3, step1=-1, start2=0, stop2=-2, step2=-1,
)
Traceback (most recent call last):
  File "/home/runner/work/pandas/pandas/pandas/tests/indexes/ranges/test_setops.py", line 463, in test_range_difference
    assert_range_or_not_is_rangelike(result)
  File "/home/runner/work/pandas/pandas/pandas/tests/indexes/ranges/test_setops.py", line 441, in assert_range_or_not_is_rangelike
    assert not (diff == diff[0]).all()
AssertionError: assert not True
 +  where True = <built-in method all of numpy.ndarray object at 0x7f0d01937390>()
 +    where <built-in method all of numpy.ndarray object at 0x7f0d01937390> = Int64Index([-3], dtype='int64') == -3.all

looks like hypothesis found an issue :->

[jbrockmendel]

looks like hypothesis found an issue :->

yah just started a branch for this...