Hi Yossi,
I have been using Agavi for 6 years now thereby shipping several sites (big video and news portals) with a very high load.
Every time the shit hit the fan and a site's performance was dying, in the end the framework wasn't the one to blame.
Rather the problems were mostly home brewed and located within the domain layer, persistence- or caching tier. (varnish to the rescue ^^)
So I guess for a good performance you could take either Agavi or Symfony and achieve similar results.
I personally favor Agavi because it is strongly opinionated and for it's architecture (filters, output-types, routing etc.) and sophisticated xml configuration.
In the end it's mostly (not all ^^) a question of taste and depends on what kinda app you are targeting (backend, frontend etc.) and how long you'll be maintaining it.
The project is not dead I guess as I know of several companies besides the one I am working for that are very actively using it.
But it is true that the github migration has been taking quite a while and I would love finally seeing it done sometime the next month(s?)
In short:
- no performance problems unless you build them ^^
- it is not dead and I hope it'll gain momentum again soon
Greetz
Thorsten