On Wed, Aug 19, 2009 at 4:08 AM, Daniel Stenberg<daniel_at_haxx.se> wrote:
> Hello friends,
>
> Georg Lippitsch reported that he could reach twice the download performance
> with libcurl simply by upping CURL_MAX_WRITE_SIZE to 40960.
>
> As this is bound to be dependent on the TCP stack, I would be very
> interested to get to hear from others if changing CURL_MAX_WRITE_SIZE (to
> whatever value really) will change the transfer speed in any significant
> way.

Windows 2003 and below have a maximum I/O size of 64KB -- anything
more is broken down into 64KB chunks. Windows Vista removed this
limitation. It seems plausible that with a high enough transfer
speed, a performance gain could be had from reducing expensive I/O
calls.

-- 
Cory Nelson
http://int64.org