Antoine Pitrou <[EMAIL PROTECTED]> added the comment: Hi Alexandre,
I first tried to use a (non-preallocated) bytearray object and, after trying several optimization schemes, I found out that the best one worked as well with an immutable bytes object :) I also found out that the bytes <-> bytearray conversion costs can be noticeable in some benchmarks. The internal buffer is rarely reallocated because the current offset inside it is remembered instead; also, when reading bytes from the underlying unbuffered stream, a list of bytes objects is accumulated and then joined at the end. I think a preallocated bytearray would not make a lot of sense since we can't readinto() an arbitrary position, so we still have a memory copy from the bytes object returned by raw.read() to the bytearray buffer, and then when returning the result to the user as a bytes object we have another memory copy. In other words each read byte is copied twice more. Of course, if this code was rewritten in C, different compromises would be possible. cheers Antoine. __________________________________ Tracker <[EMAIL PROTECTED]> <http://bugs.python.org/issue2523> __________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
