Re: Patch to eliminate user space memory copying in 'cp'

Jim Meyering <[email protected]> wrote:
> "Spinka, Kristofer" <[email protected]> wrote:
>>   You will have to incorporate the check for sendfile, but otherwise
>> this patch should avoid the most common kernel<->user space read/write
>> transitions.
>
> Thank you for that patch.  It looks like a fine optimization.
>
> I'll work on integrating it after coreutils-5.0.

After a few simple tests, I don't see any performance
benefit to using sendfile.  Do you have evidence that
using sendfile is worthwhile?