> Instead of making changes to my application to use > sendfile(..), is it possible for me to enable zerocopy > in 2.4.19 kernel (using a patch or something) so that > tx checksum can be offloaded to the h/w for every TCP > packet? tx checksum offload and zerocopy are two different things. checksum offload doesnt require zerocopy enabled. It can be done for both sendmsg() and sendfile() code paths, but provides significant gain only in the sendfile() code path which has eliminated the expensive user->kernel copy. In the sendmsg() case, the checksum is computed while doing the copy operation. Doing zerocopy on the sendmsg() code path is nontrivial and the end result is really sendfile(). thanks, Nivedita - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
