$ ./python -m timeit -s "x = b'a' * int(1E7)" "hash(x)"

Note that hash calculated only once.  Add -n 1 option and use a larger data.

> If somebody likes to play with the algorithm:

$ ./python -m timeit -n 1 -s "t = 'abcdefgh' * 10**8"  "hash(t)"
1 loops, best of 3: 4.86 sec per loop

Current hash algorithm runs 3.43 sec, V8's algorithm runs 2.44 sec.

With simple optimization I got 3.62 sec, only 6% slower than the current.

  #define U8TO64_LE(p) ((u64)((u32 *)(p))[0] | ((u64)((u32 *)(p))[1] << 32))