Oracle 9i optimization.. something wrong?

Hi to all,

I manage a Oracle 9i server on SuSE 7.2 linux box. The server is a Pentium III 800Mhz with 512Mb of RAM. It seems too slow on some querys. I have some questions.. and I hope somebody can help me...

• The initial database configuration file is that in /opt/oracle/product/9.0.1/admin/<sidname>/pfile/init<sidname>.ora ?
• If I change parameters with Instance Manager (for example shared_pool:_size) where are they stored?

    In Instance Manager i have shared_pool_size=117440512,     in init.ora shared_pool_size=62428800     in init<sidname>.ora shared_pool_size=80440512

   what his the real one?

   The other parameters are (from Instance Manager)

   db_block_size = 8192
   db_cache_size = 67108864
   shared_pool_size = 117440512
   log_buffer = 524288

• Can someone tells me if these values are wrong for my hardware configuration, or simply tell me if exists a tool for optimize them?

Thanks in advance.

(sorry for my english!)

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Mario Libraro
Web Applications Developer