Subject: Re: TCP socket buffers automatic sizing
To: None <firstname.lastname@example.org>
From: Blair Sadewitz <email@example.com>
Date: 07/21/2007 20:29:17
I should note that, as Steve Bellovin reported, I've gotten roughly
the same performance improvement simply by increasing the socket
buffer size. Of course, this can be a waste, but waste is always
relative to reward. ;)
As I said before, I haven't tested this systematically, but with
ftp/http transfers, it seems that I don't notice much benefit until I
hit around 1MiB/s. At ~2MiB/s, downloads from a site nearby seem to
run on average about 25% faster.
I wonder if there have been any reports of this feature being abused
as you describe on FreeBSD hosts for e.g. DoS attacks.
There is also some interesting stuff at
http://www.psc.edu/networking/projects (the corresponding FTP URL has
tarballs if the link to the file you want is broken). There's lots of
code for NetBSD, albeit from around the 1.6.2 days.