Sean Chittenden <sean@chittenden.org> writes:
> Absolutely! Is this a simple benchmark? Yup. Do I think it
> simulates PostgreSQL? Eh, not particularly.
This would be on what OS? What hardware? What size test file?
Do the "iterations" mean so many reads of the entire file, or
so many buffer-sized read requests? Did the mmap case actually
*read* anything, or just map and unmap the file?
Also, what did you do to normalize for the effects of the test file
being already in kernel disk cache after the first test?
regards, tom lane