Solaris 9 Tuning Tips requested

I'm looking for suggestions on tuning Solaris 9 for a SunFire 890 (Ultra
IV chips) connected to an Hitachi 9500V running PostgreSQL 7.4.

Database is approx 160GB in size with a churn of around 4GB per day (2
GB updated, 2GB inserted, very little removed). It's a mixture of OLTP
and reporting.

5% is reports which do trickle writes 95% is short (30 second or less)
transactions with about 10 selects, 10 writes (inserts, updates, deletes
all mixed in) affecting 150 tuples.

Thanks for any tips -- particularly Solaris kernel tuning or oddities in
Disk IO or configuration settings as they related to Solaris (as they
differ from an Intel).

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