Re: Oracle Memory Configuration (newbie)

Steve -

thanks for the info, but could you please clarify how you arrived at some of the numbers?

on NT - the I/O size is 64 KB.
As I understand things, the db_file_multiblock_read_count * db_block_size should equal a multiple of the OS I/O size. For a small database, the multiplier should be 1. So IMHO:

db_file_multiblock_read_count = 16
hash_multiblock_io_count = 16
sort_read_fac = 16

> db_block_size = 4096
> db_file_multiblock_read_count = 32
> hash_multiblock_io_count = 32
> sort_read_fac = 32

Also:

> sort_area_size = 2097152
> sort_area_retained_size = 262144

I would recommend starting with sort_area_size at 1/2 MB, and moving up. If the sorts aren't going to disk at all, you'll have no idea as to what setting is optimal.
If you have a non-trivial number of user connections, 2 MB each will add up in a hurry - for nothing.
You'd be better off allocating memory for hash_area_size and using hash joins where they make sense.

> db_block_lru_latches = 2

This should be the same as the number of db_writer_processes NT only supports 1 db_writer - multiple db_writers are not supported - even on 8.1.7.
This can induce corruption - according to the platform-specific release notes.

I still have an NT database on 7.3.4.5.2 in the office, but most are now on 8.1.6.3.4 or 8.1.7.0.2.

thanks.

Paul Received on Sat Apr 14 2001 - 13:22:57 CDT