Re: [hybi] Background info: Properties of sendfile()

["Roy T. Fielding" <[e-mail]>]

On Aug 5, 2010, at 5:49 PM, Jamie Lokier wrote:

> It's time to explain sendfile() better.
> 
> 0. Nearly all OSes used for web serving have something called
>   sendfile() or under a different name.  It has become a standard
>   method used in high performance static servers, and is beginning to
>   be used in dynamic servers that do smart caching.  It is given an
>   open file handle and range, and writes content of that file to a
>   TCP socket as efficiently as possible.  Some OSes allow contents of
>   process memory to be sent as well.

Unfortunately, you should also be aware that nearly all OSes have
severe kernel bugs in their implementations of sendfile and seem
to be getting progressively worse over time, to the point where
Apache httpd needs to disable it by default.  I don't know why.

....Roy