http://bsd.slashdot.org/article.pl?sid=03/11/05/1536226&mode=thread&tid=122&tid=185&tid=190&threshold=-1:


  `Research conducted at MIT [mit.edu] found BSD's filesystem implementation
   to be "very poorly performing." [1]   Even BSD's acclaimed TCP/IP stack
   has lagged behind, according to this study. [2]'

[1] http://web.mit.edu/tytso/www/linux/ext2intro.html

[2] http://cs-tr.cs.rice.edu/Dienst/Repository/2.0/Body/ncstrl.rice_cs/TR99-335/postscript