PEP 454: remove Snapshot.timestamp attribute

pep-0454.txt

@@ -153,7 +153,7 @@ Main functions
     The function uninstalls hooks on Python memory allocators, so the
     overhead of the module becomes null.
 
-    Call ``get_traces()`` or ``take_snapshot()`` function to get traces
+    Call ``take_snapshot()`` function to take a snapshot of traces
     before clearing them.
 
     See also ``start()`` and ``is_tracing()`` functions.
@@ -168,8 +168,8 @@ Main functions
     ``tracemalloc`` module started to trace memory allocations nor
     memory blocks ignored by filters (see ``get_filters()``).
 
-    Tracebacks of traces are limited to ``traceback_limit`` frames. Use
-    ``set_traceback_limit()`` to store more frames.
+    Tracebacks of traces are limited to ``get_traceback_limit()``
+    frames. Use ``set_traceback_limit()`` to store more frames.
 
     The ``tracemalloc`` module must be tracing memory allocations to
     take a snapshot, see the the ``start()`` function.
@@ -214,14 +214,14 @@ allocation occurred. See the ``Trace`` class.
     function to measure the overhead and the ``add_filter()`` function
     to select which memory allocations are traced.
 
-    If the limit is set to ``0`` frame, the traceback ``(('<unknown>',
-    0),)`` will be used for all traces.
+    If the limit is set to ``0`` frame, a traceback with a frame will be
+    used for all traces: filename ``'<unknown>'`` at line number ``0``.
 
     Use the ``get_traceback_limit()`` function to get the current limit.
 
-    The ``PYTHONTRACEMALLOC`` environment variable and the ``-X``
-    ``tracemalloc=NFRAME`` command line option can be used to set a
-    limit at startup.
+    The ``PYTHONTRACEMALLOC`` environment variable
+    (``PYTHONTRACEMALLOC=NFRAME``) and the ``-X`` ``tracemalloc=NFRAME``
+    command line option can be used to set the limit at startup.
 
 
 Filter functions
@@ -306,7 +306,7 @@ Filter
 
 ``filename_pattern`` attribute:
 
-    Filename pattern (``str``) of the filter.
+    Filename pattern of the filter (``str``).
 
 ``all_frames`` attribute:
 
@@ -315,7 +315,8 @@ Filter
     checked.
 
     This attribute is ignored if the traceback limit is less than ``2``.
-    See the ``get_traceback_limit()`` function.
+    See the ``get_traceback_limit()`` function and
+    ``Snapshot.traceback_limit`` attribute.
 
 
 Frame
@@ -343,12 +344,12 @@ Snapshot
 
     Snapshot of traces of memory blocks allocated by Python.
 
-    The ``take_snapshot()`` function create a snapshot instance.
+    The ``take_snapshot()`` function creates a snapshot instance.
 
 ``apply_filters(filters)`` method:
 
-    Create a new ``Snapshot`` instance with the filtered ``traces``,
-    *filters* is a list of ``Filter`` instances.
+    Create a new ``Snapshot`` instance with the filtered ``traces``
+    sequence, *filters* is a list of ``Filter`` instances.
 
     If *filters* is an empty list, return a new ``Snapshot`` instance
     with a copy of the traces.
@@ -356,9 +357,8 @@ Snapshot
 
 ``compare_to(old_snapshot: Snapshot, group_by: str, cumulative: bool=False)`` method:
 
-    Compute the differences with an old snapshot *old_snapshot*. Get
-    statistics as a sorted list of ``StatisticDiff`` instances, grouped
-    by *group_by*.
+    Compute the differences with an old snapshot. Get statistics as a
+    sorted list of ``StatisticDiff`` instances grouped by *group_by*.
 
     See the ``statistics()`` method for *group_by* and *cumulative*
     parameters.
@@ -385,7 +385,7 @@ Snapshot
 
 ``statistics(group_by: str, cumulative: bool=False)`` method:
 
-    Get statistics as a sorted list of ``Statistic`` instances, grouped
+    Get statistics as a sorted list of ``Statistic`` instances grouped
     by *group_by*:
 
     =====================  ========================
@@ -398,9 +398,9 @@ Snapshot
 
     If *cumulative* is ``True``, cumulate size and count of memory
     blocks of all frames of the traceback of a trace, not only the most
-    recent frame. The cumulative mode can only be used with key types
-    ``'filename'`` and ``'lineno'`` with ``traceback_limit`` greater
-    than ``1``.
+    recent frame. The cumulative mode can only be used with *group_by*
+    equals to ``'filename'`` and ``'lineno'`` and ``traceback_limit``
+    greater than ``1``.
 
     The result is sorted from the biggest to the smallest by:
     ``Statistic.size``, ``Statistic.count`` and then by
@@ -409,8 +409,8 @@ Snapshot
 
 ``traceback_limit`` attribute:
 
-    Maximum number of frames stored in the traceback of ``traces``: see
-    the ``get_traceback_limit()`` function.
+    Maximum number of frames stored in the traceback of ``traces``:
+    result of the ``get_traceback_limit()`` when the snapshot was taken.
 
 ``traces`` attribute:
 
@@ -420,11 +420,6 @@ Snapshot
     The sequence has an undefined order. Use the
     ``Snapshot.statistics()`` method to get a sorted list of statistics.
 
-``timestamp`` attribute:
-
-    Creation date and time of the snapshot, ``datetime.datetime``
-    instance.
-
 
 Statistic
 ---------
@@ -525,7 +520,7 @@ Traceback
     module failed to get a frame, the filename ``"<unknown>"`` and the
     line number ``0`` are used. If it failed to get the traceback or if
     the traceback limit is ``0``, the traceback only contains a frame:
-    filename ``'<unknown>'`` and line number ``0``.
+    filename ``'<unknown>'`` at line number ``0``.
 
     When a snapshot is taken, tracebacks of traces are limited to
     ``get_traceback_limit()`` frames. See the ``take_snapshot()``