vacuum locks up database

Postgres ver. 7.3.1 on HPUX:

I have a fairly large database. My big table has about 32,000,000 rows with
3 indexes. When I run vacuumdb and it gets to the big table, it churns for
about 3 hours and starts blocking other database users. Simple inserts into
that table timeout after 15 minutes.

I have increased vacuum_mem = 23768 and had no effect on the problem.

I have nice'd the psql client -19, but the resulting postgres process is
still running at it's original priority.

Is there anyway to force vacuum to run more as a background job and not
block others from accessing the database during the vacuum process?

What are the trade-offs for pushing vacuum_mem up even higher? Would that
help?

Bill Jones
Systems Architect
Middleware Services
Wells Fargo Services Company
Office --415.243.1364
PCS -- 415.254.3831 (4152543831(at)mobile(dot)att(dot)net)

Views expressed are mine. Only in unusual circumstances are they shared by
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