These are largely pre-sorted, but not fully when you have merged data. This
uses timsort to speed that up a bit.
In particular, the comparison of various sorts break down to (for a
~32,000,000 record capture.
g_array_sort_with_data() => 3.9 seconds
qsort_r() = > 3.7 seconds
gtk_tim_sort() => .79 seconds