I spent a few days last week optimising PackageKit. I first added a couple of huge 350ms+ optimisations when using Hawkey. Then I turned my attention to the daemon itself and after adding a lot of profiling hooks to packagekitd, I recoiled in horror the amount of time it took to do simple things that everyone assumed would be fast.
A lot of unused functionality that was hurting transaction start times was removed. Certain core string functions were made fractions of ms faster and transactions a few hundreds of ms quicker in a few places, etc. The final result is that everything feels rather much speedier. Time-critical features like
command-not-found and search-as-you-type now actually feel useful.
$ time pkcon search name powertop &> /dev/null real0m0.082s
If you want to try out the new hotness, install the Fedora 20 update, enable the new hawkey backend and make sure you give karma. There’s also no more Zif backend in PackageKit, as hawkey is now faster and more reliable for all operations.