Well, first off, thank you guys for the long way kmail has come since about 4.0.something. By 4.4 it had gotten stable enough to replace thunderbird (which had been p*ing me off for quite some time), and nowadays it's simply the greatest mail application one could ever imagine. I just LOVE the configurability. Of course, the same goes for the rest of KDE. Why else would I bother dealing with the (luckily by now) occasional regression that disturbs my everyday workflow? But regressions aside, one big issue remains: Performance
I'm really happy we've finally gotten rid of busy-waiting with like a 100 ms sleep and instead make proper use of dbus (I'm thinking of the 3.5 kicker...). BUT it looks like we've traded that for data structures that cause an awful lot of pointer dereferencing and other memory access. Maybe I'm very sensitive to this, but in a proper UI I expect reaction times far below 50 ms for things like opening a menu. So I'm really wishing for an improvement of overall architectural efficiency. Please minimize memory access. I know that means more code, more data redundancy and therefore greater memory requirements, but I think it should be worth it. RAM is cheap and I don't need KDE in a memory constrained VM or something.