shared_buffers/effective_cache_size on 96GB server

Hi everyone,

I have a Postgresql 9.1 dedicated server with 16 cores, 96GB RAM and RAID10
15K SCSI drives which is runing Centos 6.2 x64. This server is mainly used
for inserting/updating large amounts of data via copy/insert/update
commands, and seldom for running select queries.

Here are the relevant configuration parameters I changed:

shared_buffers = 10GB
effective_cache_size = 90GB
work_mem = 32MB
maintenance_work_mem = 512MB
checkpoint_segments = 64
checkpoint_completion_target = 0.8

My biggest concern are shared_buffers and effective_cache_size, should I
increase shared_buffers and decrease effective_cache_size? I read that
values above 10GB for shared_buffers give lower performance, than smaller
amounts?

free is currently reporting (during the loading of data):

$ free -m
total used free shared buffers cached
Mem: 96730 96418 311 0 71 93120
-/+ buffers/cache: 3227 93502
Swap: 21000 51 20949

So it did a little swapping, but only minor, still I should probably
decrease shared_buffers so there is no swapping at all.

Thanks in advance,
Strahinja