Raw Logical Volumes vs. Unix File Systems

Oracle DBAs,

Perhaps I need to dig up the DBA FAQ (I read through the user one), but I need some information about creating Oracle databases on Raw Logical Volumes vs. standard Unix file systems.

What are the advantages? Are they that much faster? We have a 6-8 GB Oracle 7 database sitting on an RS/6000 590, and we are starting to see a major slowdown now that our tables have grown so large. Our DBA (I know close to nothing about being a DBA) just returned from Tuning class, and she will be analyzing the database and making some changes soon (adding indexes, optimizing queries, defragmenting the system, etc.).

One of the options that has come up is, do we want to move to a raw logical volume? I'm worried that we'll lose something in the process, but I'm willing to try it if it helps with speed. Have any of you had good luck with this? Has anyone else done it under AIX 3.2.5? Any problems?

I'm clueless to the issues involved, and I wanted to see if there was any good Usenet wisdom out there on the subject. If I get any e-mail replies, I can form them into a summary and post it.

Thanks in advance,

-- 
Stephen O. Pace                                          pace_at_shell.com
Shell Oil Company                                          713/544-7929