Note: This keyword is no longer recommended as of March 2019.
Forces all checkpoints but the final checkpoint to use a single system call to flush file system buffers instead of individual calls for each file to ctsave(). The motivation is that a call to flush the buffers for a specified file may require significant time whether or not the file has many updated pages in the file system cache; hence one flush of all the buffers may be faster than repeated calls for individual files. For Unix systems this implementation automatically invokes sync() unless another definition is already in place. No other platform has a default definition.