James Carlson writes: > The original ARC cases for sendfile and sendfilev (2000/433 and > 2000/279) discussed this very issue. The case owner pointed out that, > besides targeting a particular application, the folks implementing it > weren't prepared to test all the possible combinations of vnode types > to make sure that they'd all work as expected, and thus they wanted to > limit the scope as much as possible.
In addition to being flexible, it would be nice if it were able to do zero-copy more frequently. I spent quite a lot of time with dtrace and the OpenSolaris sources trying to figure out what ducks I needed to have in a row to avoid memory copies in the kernel when I implemented TCP_SENDFILE support for Solaris in netperf to benchmark my 10GbE NIC. As to Linux's UDP sendfile support: Does anybody know the API? Does it require the application to make a syscall every MTU-epsilon bytes, or is there a way to get the kernel to break up the packets? Whatever it does, is it actually useful in the digital video environment? Drew _______________________________________________ networking-discuss mailing list [email protected]
