For most databases (I don't know Pg, so it may be different), it's much faster to have a few large 
  INSERT INTO table (a, b, c)
  VALUES (z, y, x), (w, v, u), (t, s, r), ...

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queries, than to do a round trip for each row inserted.

And sometimes, it's faster to first drop all the indices, and recreate them after the inserts are done. But that requires some benchmarking for each case.

several seconds for every 100K INSERTs
That doesn't sound that slow to me. Perhaps you need to hire a Pg specialist to tweak your database.

In reply to Re: Speeding up Postgres INSERTs by JavaFan
in thread Speeding up Postgres INSERTs by punkish

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