René Scharfe <l....@web.de> writes: > The difference is about the same as the one between: > > $ time git log --format="" >/dev/null > > real 0m0.463s > user 0m0.448s > sys 0m0.012s > > and: > > $ time git log --format="%h" >/dev/null > > real 0m1.062s > user 0m0.636s > sys 0m0.416s > > With caching duplicates are basically free and without it short > hashes have to be looked up again. Other placeholders may reduce > the relative slowdown, depending on how expensive they are.
I think the real question is how likely people use more than one occurrence of the same thing in their custom format, and how deeply they care that --format='%h %h' costs more than --format='%h'. The cost won't of course be double (because the main traversal costs without any output), but it would be rather unreasonable to expect that --format='%h %h %h %h %h' to cost the same as --format='%h'; after all, Git is doing more for them ;-) So in that sense, I am actually OK if we decide to remove the caching. > Forgot a third option, probably because it's not a particularly good > idea: Replacing the caching in pretty.c with a short static cache in > find_unique_abbrev_r(). Indeed.
