Storing a dynahash for an entire connection or transaction?

I've now got to custom datatypes that map from an int2 value on disk to 
a string by way of a table for each. Currently, I load these tables into 
a dynahash per function call (fcinfo->flinfo->fn_extra). This is working
great is most situations. The problem situation is where there are many
queries (often INSERTS) that need to happen in a short amount of time.
This causes reloads of the dynahash (or hashes) for each query, making
them orders of magnitude slower than when these columns were varchar.

What I'd like to do is change the way I store this hash so that it 
doesn't need to be as frequently updated. I'm open to most any solution. 
One type rarely ever has new values (maybe once every several months) 
and the other gets new values once a night.

Thoughts?

Greg


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