With server configuration and application functional we cannot conclude postgresql.conf, application behavior need to consider(mandatory)
but, can give some ideal way of calculation
1) shared_buffers can be 7-8% of database size under condition having proper indexes with size not greater then 10-15% of respective table size,
2) work_mem can be 8mb if database size under 100-120gb with point#1
3) maintanance_work_mem can be 512mb if database size under 100-120gb and any table max size under 0-2GB
4) checkpoint_segments = 16
5) all scan parameters "on"
6) autovacuum = on ##### if transactions on tables are under 0-30% per day
autovacuum_vacuum_scale_factor = 0.2
autovacuum_analyze_scale_factor = 0.1
7) effective_cache_size = 64-96GB
Note: 1) may need changes based on application behavior, specially if sorting and full-table-scans and transactions are very high.
2) regular maintenance is required to control database size and performance
3) only some parameters defined