postgresql performance tuning

Hello,

I have a question on postgres's performance tuning, in particular, the
vacuum and reindex commands. Currently I do a vacuum (without full) on all
of my tables. However, its noted in the docs (e.g.
http://developer.postgresql.org/docs/postgres/routine-reindex.html)
and on the lists here that indexes may still bloat after a while and hence
reindex is necessary. How often do people reindex their tables out
there? I guess I'd have to update my cron scripts to do reindexing too
along with vacuuming but most probably at a much lower frequency than
vacuum.

But these scripts do these maintenance tasks at a fixed time (every few
hours, days, weeks, etc.) What I would like is to do these tasks on a need
basis. So for vacuuming, by "need" I mean every few updates or some such
metric that characterizes my workload. Similarly, "need" for the reindex
command might mean every few updates or degree of bloat, etc.

I came across the pg_autovacuum daemon, which seems to do exactly what I
need for vacuums. However, it'd be great if there was a similar automatic
reindex utility, like say, a pg_autoreindex daemon. Are there any plans
for this feature? If not, then would cron scripts be the next best
choice?

Thanks,
Ameet