Answers for OpenACS 5.0.0 standard install:
No volatile data goes into /usr/local/aolserver/servers.
On (some) debian systems, /usr/local/pgsql/data is now /var/lib/postgres/data. Installing pgsql from source puts data in /var/lib/pgsql.
On OpenACS.org, the database is 4 million records, the text backup dump is 450Mb uncompressed, 370Mb in the data directory. The biggest growth on the file system is the logs, then the content repository (if you have much blob data). The code base is 10-100 mb. OpenACS.org has 252M in the content repository, 80M of package code, and 80M of www content, and the access log + error log totals 20Mb per day.
/web is going away, to be replaced by /var/lib/aolserver, as the docs indicate. However I've gotten sick of typing /var/lib/aolserver and tend to symlink /web back in.
The next step, for 5.2 or 5.3, will be to partition the static code from the volatile data, for better security and for easier backup/deployment/clustering. This should just be a matter of adjusting config.tcl and the instructions.
