In 11Gr2 this parameter can be used to CPU caging. -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Martin Berger Sent: Wednesday, September 16, 2009 4:47 PM To: Dave.Herring@xxxxxxxxxx Cc: nkodner@xxxxxxxxx; oracle-l@xxxxxxxxxxxxx Subject: Re: best way to invoke parallel in DW loads? Dave, just a small correction: (at least in 11.1.0.7, have not tested 10gR2) these parameters are calculated from CPU_COUNT: __db_cache_size __shared_pool_size _cursor_db_buffers_pinned _db_block_buffers _db_block_lru_latches _enqueue_hash_chain_latches _enqueue_locks _flashback_generation_buffer_size _kghdsidx_count _log_parallelism_max _log_simultaneous_copies _num_longop_child_latches _parallel_min_message_pool _shared_server_num_queues _small_table_threshold _spin_count _sqlmon_max_plan cpu_count db_writer_processes log_buffer parallel_max_servers - see also http://berxblog.blogspot.com/2009/01/instance-parameters-derived-from.html > CPU_COUNT -> please don't change this. Let Oracle figure it out. In 10g > it's an underscore parameter and it doesn't make much sense to mess with it. > The only impact that a manual change will have (I believe) is the default > parallel degree, calculated by CPU_COUNT * PARALLEL_THREADS_PER_CPU. Neil, if you want to tweek there, be careful and make good records about all related changes for tracability. hth Martin -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l