1 # memorytop requires Python 3.4

     2 #

     3 # Usage: set PYTHONTRACEMALLOC=n in the environment of the hg invocation,

     4 # where n>= is the number of frames to show in the backtrace. Put calls to

     5 # memorytop in strategic places to show the current memory use by allocation

     6 # site.

     7 

     8 import gc

     9 import tracemalloc

    10 

    11 

    12 def memorytop(limit=10):

    13     gc.collect()

    14     snapshot = tracemalloc.take_snapshot()

    15 

    16     snapshot = snapshot.filter_traces(

    17         (

    18             tracemalloc.Filter(False, "<frozen importlib._bootstrap>"),

    19             tracemalloc.Filter(False, "<frozen importlib._bootstrap_external>"),

    20             tracemalloc.Filter(False, "<unknown>"),

    21         )

    22     )

    23     stats = snapshot.statistics('traceback')

    24 

    25     total = sum(stat.size for stat in stats)

    26     print("\nTotal allocated size: %.1f KiB\n" % (total / 1024))

    27     print("Lines with the biggest net allocations")

    28     for index, stat in enumerate(stats[:limit], 1):

    29         print(

    30             "#%d: %d objects using %.1f KiB"

    31             % (index, stat.count, stat.size / 1024)

    32         )

    33         for line in stat.traceback.format(most_recent_first=True):

    34             print('    ', line)

    35 

    36     other = stats[limit:]

    37     if other:

    38         size = sum(stat.size for stat in other)

    39         count = sum(stat.count for stat in other)

    40         print(

    41             "%s other: %d objects using %.1f KiB"

    42             % (len(other), count, size / 1024)

    43         )

    44     print()