Re: hash_area_size

Joel Garry <joelga_at_pebble.org> wrote in article <slrn6mrcdt.ta3.joelga_at_pebble.org>...
> Example 5, page 19-53 of the Oracle8 Server Tuning Manual seems to
show the
> hash area is in addition to the sort area.

If in doubt, don't assume the manuals are correct !

Experiment:

	set hash_area_size =2M
	set sort_area_size = 2M
	start database

	run top to see size of dedicated shadow-processes

a)	At steady state (small create table, create index, etc. shadow
shows 10100K
b)	Execute statement to do large sort
		shadow jumps to 12184K
c)	terminate session

Repeat,  but execute statement to do large hash
		shadow jumps to 12184K

Repeat doing sort, then hash
		shadow is stable as 12184K

Repeat doing hash then sort
		shadow is stable at 12184K

It really looks as if memory allocated for sort_area_size is interchangeable
with memory allocated for hash_area_size

Jonathan Lewis Received on Fri May 29 1998 - 10:58:49 CDT