Re: [PATCH 4/4] diffcore-pickaxe: optimize by trimming common initial and trailing parts

Junio C Hamano [off-list ref] writes:

With this optimization in place, the following query in the Linux kernel
repository on my machine becomes about 40% faster:

$ STRING='Ensure that the real time constraints are schedulable.'
$ git log -S"$STRING" HEAD -- kernel/sched.c >/dev/null

(Before the patch, best of 5 runs)
5.59user 0.15system 0:05.74elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+39956minor)pagefaults 0swaps

(After the patch, best of 5 runs)
3.04user 0.17system 0:03.23elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+49697minor)pagefaults 0swaps

    
The file "kernel/sched.c" has roughly 900 changes applied to it, and over
its lifetime, it has grown from 5kB to 9kB in size.

I suspect a larger file might see a bigger performance boost.