Comment 11 for bug 947664

On 12-05-30 01:11 PM, Raphaël Hertzog wrote:
>
> sync_file_range() is something different, it just tells the filesystem to
> start the writeback, it doesn't wait for it to have happened (contrary to
> fsync()).
>
> So it should be irrelevant for the time lost, unless Linux's NFS driver
> has a poor handling of this Linux-specific function.

Well, I tried NOOPing it with an LD_PRELOAD:

sync_file_range(int fd, off64_t offset, off64_t nbytes,
                unsigned int flags) {

        printf("sync_file_range()\n");
        return 0;
}

but that doesn't seem to have helped performance any.