This is a test case for bug:

BUG 20510832 - TEST_WITH_MMAP: LOW READ/WRITE PERFORMANCE IF COMPARE TO SOLARIS

It works this way:
1) Allocates a memory region using mmap(MAP_ANONYMOUS)
2) Tries to write/read to this region using a specified block size
3) Deallocates this region using munmap()
4) Measures the time required for each of the above steps

The initial idea is to use this test case to verify whether the TSB size
on Linux is less than on Solaris. To check that you need to run:

on Linux:

./test_with_mmap -i 10 -r 16g -b 8k

on Solaris:

./test_with_mmap -i 10 -r 16g -b 8k -p 8k

and compare the results. They should be more-or-less the same.

We may also use this test case to track regressions between kernel versions.

On Linux, by default, the default page size is used for allocating the region.
However, you may allocate it with Huge Pages (-h). On Solaris the page size
for the region is selected by (-p).