Optimization required for multiple insertions in PostgreSQL

[siva palanisamy <psivait@xxxxxxxxx>]

I basically have 3 tables. One being the core table and the 
other 2 depend on the 1st. I have the requirement to add upto 70000 
records in the tables. I do have constraints (primary & foreign 
keys, index, unique etc) set for the tables. I can't go for bulk import 
(using COPY command) as there is no standard .csv file in requirement, 
and the mapping is explicitly required plus few validations are 
externally applied in a C based programming file. Each record details 
(upto 70000) will be passed from .pgc (an ECPG based C Programming file)
 to postgresql file. It takes less time for the 1st few records and the 
performance is turning bad to the latter records! The result is very sad
 that it takes days to cover upto 20000! What are the performance 
measures could I step in into this? Please guide me