Serhiy Storchaka added the comment: Python interpreter itself takes 20-30 MB of memory. Using it on a machine that has no few tens of free memory doesn't make much sense. MicroPython can be an exception, but it has special modules for low-level programming.
If you need to proceed so large bytearray that creating yet one copy of it is not possible, it can be translated by separate elements or smaller chunks. $ ./python -m perf timeit -s "table = bytes(range(256)).swapcase(); data = bytearray(range(256))*1000" -- "for i in range(len(data)): data[i] = table[data[i]]" Median +- std dev: 205 ms +- 10 ms $ ./python -m perf timeit -s "table = bytes(range(256)).swapcase(); data = bytearray(range(256))*1000" -- "for i in range(0, len(data), 100): data[i:i+100] = data[i:i+100].translate(table)" Median +- std dev: 12.9 ms +- 0.6 ms $ ./python -m perf timeit -s "table = bytes(range(256)).swapcase(); data = bytearray(range(256))*1000" -- "for i in range(0, len(data), 1000): data[i:i+1000] = data[i:i+1000].translate(table)" Median +- std dev: 3.12 ms +- 0.22 ms $ ./python -m perf timeit -s "table = bytes(range(256)).swapcase(); data = bytearray(range(256))*1000" -- "for i in range(0, len(data), 10000): data[i:i+10000] = data[i:i+10000].translate(table)" Median +- std dev: 1.79 ms +- 0.14 ms Translating by chunks also works with data that can't be fit in memory at all. You can mmap large file or read and write it by blocks. In-place bytearray method wouldn't help in this case. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue17301> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
