A look at rsync performance

No, I think the take-home of this isn't the fact that "rsync which does checksumming and read comparsions is slower than tar/cp/cat" but rather that "the kernel does strange things around rsync and can be made to perform better"

Read this as a very detailed bug report to the compound of the system. Explaining both in part what goes wrong, where it goes wrong, and something about how to fix parts of it.