Application Provided Checksums

摘要

Transport protocol checksum computation is one of the main processing overheads in a TCP/IP stack. A number of techniques have been proposed to alleviate the cost of checksum computation. Most of them have concentrated on optimizing the checksum where it is implemented as part of the kernel. We argue that for performance it is better if application provides the checksum to the kernel rather than the kernel computing it. We describe the system call and its implementation using which an application can provide checksum to the kernel. We discuss various approaches that applications can use to come up with the checksums for their data buffers.