New submission from Irmen de Jong <ir...@razorvine.net>: Pickling of bytearrays is quite inefficient right now, because bytearray's __reduce__ encodes the bytes of the bytearray into a str. A pickle made from a bytearray is quite a bit larger than necessary because of this, and it also takes a lot more processing to create it and to convert it back into the actual bytearray when unpickling (because it uses bytearray's str based initializer with encoding).
I've attached a patch (both for the default 3.x branch and the 2.7 branch) that changes this to use the bytes type instead. A pickle made from a bytearray with this patch applied now utilizes the BINBYTES/BINSTRING pickle opcodes which are a lot more efficient than BINUNICODE that is used now. The reconstruction of the bytearray now uses bytearray's initializer that takes a bytes object. I don't think additional unit tests are needed because test_bytes already performs pickle tests on bytearrays. A bit more info can be found in my recent post on comp.lang.python about this, see http://mail.python.org/pipermail/python-list/2011-November/1283668.html ---------- components: Interpreter Core files: bytearray3x.patch keywords: easy, needs review, patch messages: 148627 nosy: alexandre.vassalotti, irmen, pitrou priority: normal severity: normal stage: patch review status: open title: improved efficiency of bytearray pickling by using bytes type instead of str type: performance versions: Python 2.7, Python 3.1, Python 3.2, Python 3.3, Python 3.4 Added file: http://bugs.python.org/file23812/bytearray3x.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue13503> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
