How to monitor resources on Linux.

Hello All

I have some questions on memory resources and linux. We are
currently running Dell Poweredge 2950 with dual core opeterons and 8GB
RAM. Postgres version is 7.4.17 on RHEL4. Could someone explain to me
how to best monitor the memory resources on this platform. Top shows a
high memory usage nearly all is being used. ipcs -m shows the following
output. If I am looking at this correctly each of the postgres entries
represents a postmaster with the number of connections. If I calculate
the first entry it comes to around 3.4GB of RAM being used is this
correct. We have started running into memory issues and I think we have
exhausted all the memory on the system. I think the best approach would
be to add more memory unless someone can suggest other options. We have
a 2 node cluster running about 10 separate postmasters divided evenly on
each node. Each postmaster is a separate division is our company if we
have a problems with one database not everyone is down.

0x0052ea91 163845 postgres 600 133947392 26
0x00530db9 196614 postgres 600 34529280 24
0x00530201 229383 postgres 600 34529280 21
0x005305e9 262152 postgres 600 4915200 3
0x005311a1 294921 postgres 600 34529280 28
0x0052fe19 327690 postgres 600 4915200 4

Thanks

John Allgood - Systems Admin
Turbo Logistics