all Python 3cProfilefunction

cProfile.run()

running the profiler

Profiles a string of code via exec() and prints a table: how many times each function ran and how much time it took.

Syntax

cProfile.run(command, filename=None, sort=-1)

The code runs in the namespace of the __main__ module, so the caller's local variables are invisible: cProfile.run('sorted(data)') inside main() raises NameError — use runctx() for them. With filename nothing is printed; the stats are saved to a binary file for pstats, not to text. sort='cumulative' shows straight away where time goes including nested calls.

Examples

import cProfile
def slow():
    return sum(i * i for i in range(10000))
cProfile.run('slow()', sort='cumulative')  # → ? таблица вызовов, время зависит от машины

import cProfile
def main():
    data = list(range(1000))
    try:
        cProfile.run('sorted(data)')
    except NameError as e:
        print(e)  # → name 'data' is not defined
main()

See also

Common errors

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