[Python-Dev] PEP 393 review

[Antoine Pitrou]

> - the iobench results are between 2% acceleration (seek operations),
>   16% slowdown for small-sized reads (4.31MB/s vs. 5.22 MB/s) and
>   37% for large sized reads (154 MB/s vs. 235 MB/s). The speed
>   difference is probably in the UTF-8 decoder; I have already
>   restored the "runs of ASCII" optimization and am out of ideas for
>   further speedups. Again, having to scan the UTF-8 string twice
>   is probably one cause of slowdown.

I don't think it's the UTF-8 decoder because I see an even larger
slowdown with simpler encodings (e.g. "-E latin1" or "-E utf-16le").

Thanks

Antoine.