accepting connections on the FTP port and forking children processes to
handling them. This is lower overhead than spawning ftpd from inetd and
can be a significant win on busy FTP servers. Be sure to disable ftpd in
inetd.conf if you decide to use this option.
These changes are based on similar changes I made to wu-ftpd and have
been in use on wcarchive for several months.
- set TCP_NOPUSH to keep from sending short packets at each write(2) boundary
- set SO_SNDBUF to 64k so we have a reasonable amount of buffer space
- for a regular file in binary mode which is not being restarted and is
. smaller than 16 Meg, use mmap(2) and write(2) the whole file in one big
gulp
In the most common circumstances, this should dramatically reduce the
system-call load from ftpd, since the call to write() will not return until
the entire file has been written, rather than writing just a few K at a time
in a loop.