Common platform:
Timer info: namespace(adjustable=False, implementation='clock_gettime(CLOCK_MONOTONIC)', monotonic=True, resolution=1e-09)
CPU model: Intel(R) Core(TM) i7-3630QM CPU @ 2.40GHz
SCM: hg revision=155e6fb309f5+ branch=default date="2013-05-21 21:02 +0200"
CFLAGS: -Wno-unused-result -Werror=declaration-after-statement -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes
Timer: time.perf_counter
Python unicode implementation: PEP 393
Platform: Linux-3.9.4-200.fc18.x86_64-x86_64-with-fedora-18-Spherical_Cow
Bits: int=32, long=64, long long=64, size_t=64, void*=64

Platform of campaign original.txt:
Date: 2013-06-02 09:59:33
Python version: 3.4.0a0 (default:155e6fb309f5+, Jun 2 2013, 09:59:26) [GCC 4.7.2 20121109 (Red Hat 4.7.2-8)]
Timer precision: 41 ns

Platform of campaign patched.txt:
Python version: 3.4.0a0 (default:155e6fb309f5+, Jun 2 2013, 09:57:56) [GCC 4.7.2 20121109 (Red Hat 4.7.2-8)]
Date: 2013-06-02 09:58:02
Timer precision: 46 ns

-----------------------+--------------+-------------
Length 1               | original.txt |  patched.txt
-----------------------+--------------+-------------
hash('a' * 1)          |    91 ns (*) |  96 ns (+6%)
hash('\u20ac' * 1)     |    93 ns (*) |  98 ns (+5%)
hash('\U0010ffff' * 1) |    93 ns (*) |        97 ns
-----------------------+--------------+-------------
Total                  |   277 ns (*) | 291 ns (+5%)
-----------------------+--------------+-------------

-----------------------+--------------+------------
Length 3               | original.txt | patched.txt
-----------------------+--------------+------------
hash('a' * 3)          |    98 ns (*) |       98 ns
hash('\u20ac' * 3)     |    98 ns (*) |       97 ns
hash('\U0010ffff' * 3) |    95 ns (*) |       98 ns
-----------------------+--------------+------------
Total                  |   290 ns (*) |      293 ns
-----------------------+--------------+------------

------------------------+--------------+-------------
Length 10               | original.txt |  patched.txt
------------------------+--------------+-------------
hash('a' * 10)          |   104 ns (*) |  97 ns (-7%)
hash('\u20ac' * 10)     |   102 ns (*) |  96 ns (-6%)
hash('\U0010ffff' * 10) |   100 ns (*) |        97 ns
------------------------+--------------+-------------
Total                   |   306 ns (*) | 290 ns (-5%)
------------------------+--------------+-------------

------------------------+--------------+--------------
Length 20               | original.txt |   patched.txt
------------------------+--------------+--------------
hash('a' * 20)          |   113 ns (*) |  97 ns (-14%)
hash('\u20ac' * 20)     |   108 ns (*) |  96 ns (-11%)
hash('\U0010ffff' * 20) |   114 ns (*) |  95 ns (-17%)
------------------------+--------------+--------------
Total                   |   334 ns (*) | 288 ns (-14%)
------------------------+--------------+--------------

-------------------------+--------------+--------------
Length 100               | original.txt |   patched.txt
-------------------------+--------------+--------------
hash('a' * 100)          |   197 ns (*) | 106 ns (-46%)
hash('\u20ac' * 100)     |   203 ns (*) | 107 ns (-47%)
hash('\U0010ffff' * 100) |   203 ns (*) | 107 ns (-47%)
-------------------------+--------------+--------------
Total                    |   603 ns (*) | 320 ns (-47%)
-------------------------+--------------+--------------

-----------------------------+--------------+---------------
Length 10 ** 4               | original.txt |    patched.txt
-----------------------------+--------------+---------------
hash('a' * 10 ** 4)          |  11.9 us (*) |  941 ns (-92%)
hash('\u20ac' * 10 ** 4)     |  12.1 us (*) |  947 ns (-92%)
hash('\U0010ffff' * 10 ** 4) |  11.9 us (*) |  942 ns (-92%)
-----------------------------+--------------+---------------
Total                        |    36 us (*) | 2.83 us (-92%)
-----------------------------+--------------+---------------

-----------------------------+--------------+---------------
Length 10 ** 8               | original.txt |    patched.txt
-----------------------------+--------------+---------------
hash('a' * 10 ** 8)          |   119 ms (*) | 9.85 ms (-92%)
hash('\u20ac' * 10 ** 8)     |   122 ms (*) | 9.41 ms (-92%)
hash('\U0010ffff' * 10 ** 8) |   120 ms (*) | 9.46 ms (-92%)
-----------------------------+--------------+---------------
Total                        |   361 ms (*) | 28.7 ms (-92%)
-----------------------------+--------------+---------------

---------------+--------------+---------------
Summary        | original.txt |    patched.txt
---------------+--------------+---------------
Length 1       |   277 ns (*) |   291 ns (+5%)
Length 3       |   290 ns (*) |         293 ns
Length 10      |   306 ns (*) |   290 ns (-5%)
Length 20      |   334 ns (*) |  288 ns (-14%)
Length 100     |   603 ns (*) |  320 ns (-47%)
Length 10 ** 4 |    36 us (*) | 2.83 us (-92%)
Length 10 ** 8 |   361 ms (*) | 28.7 ms (-92%)
---------------+--------------+---------------
Total          |   361 ms (*) | 28.7 ms (-92%)