Nikolaus Rath added the comment: Here's a little script to estimate the performance difference between using read1 and readinto1 to read large amounts of data. On my system, I get:
C readinto1: 4.960e-01 seconds C read1: 4.055e-01 seconds Python readinto1: 1.066e+00 seconds Python read1: 2.565e+00 seconds In other words, _pyio.BufferedReader.readinto1 is more than a factor of 2 faster than _pyio.BufferedReader.read1 and io.readinto1 is faster than io.read1 by about 20%. On its own, I think this would justify keeping an implementation of readinto1 in _pyio.BufferedReader instead of falling back on the default (that is implemented using read1). However, I believe that people who need performance are probably not using _pyio but io, so *my* argument for keeping it implemented in _pyio is to keep the implementations similiar. I found studying _pyio very helpful to understand the C code in io. If we implement BufferedReader.readinto1 in io, but not in _pyio.BufferedReader, this advantage would be reduced. That said, I am primary interested in getting readinto1 into io. So I'm happy to either extend the patch to also provide a fast readinto implementation for _pyio (to align it with io), or to remove the readinto1 implementation in _pyio. ---------- Added file: http://bugs.python.org/file34811/benchmark.py _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue20578> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
