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Dear friends,
When I execute:
SELECT (1 - (Sum(misses) / Sum(gets))) * 100
INTO v_value
FROM v$latch;
DBMS_Output.Put('Latch Hit Ratio : ' || Format(v_value));
I am getting a very low value (less than 70%). I don't see any parameter in the INIT.ORA file to increase the number of latches.
Kindly advise me how to increase the latch hit ratio. Your help will be appreciated.
db_block_lru_latches is the parameter. (this is for db block buffers only)
t
As I know, in Oracle 9i you do NOT tune the latches.
In Oracle 7,8,8i this parameter has name db_block_lru_latchesQuote:
Originally posted by ovidius
As I know, in Oracle 9i you do NOT tune the latches.
In Oracle 9i --> _db_block_lru_latches
Default value of this parameter(s) is #CPU/2
Max value for db_block_lru_latches is:
Oracle 7 --> 2*#CPU
Oracle 8,8i --> 6*#CPU
I don't sure about 9i (_db_block_lru_latches) but probably max vallue more then
6*#CPU
--------------------------------------------------
Addition (indirect) method for setup # of lru latches in 9i (8i):
BUFFER_POOL_KEEP = {integer |(BUFFERS:integer, LRU_LATCHES:integer)}
BUFFER_POOL_RECYCLE = {integer | (BUFFERS:integer, LRU_LATCHES:integer)}
[Edited by Shestakov on 04-01-2002 at 11:35 AM]
Excellent Shestakov. Many thanks for the information.Quote:
Originally posted by Shestakov
In Oracle 7,8,8i this parameter has name db_block_lru_latchesQuote:
Originally posted by ovidius
As I know, in Oracle 9i you do NOT tune the latches.
In Oracle 9i --> _db_block_lru_latches
Default value of this parameter(s) is #CPU/2
Max value for db_block_lru_latches is:
Oracle 7 --> 2*#CPU
Oracle 8,8i --> 6*#CPU
I don't sure about 9i (_db_block_lru_latches) but probably max vallue more then
6*#CPU
--------------------------------------------------
Addition (indirect) method for setup # of lru latches in 9i (8i):
BUFFER_POOL_KEEP = {integer |(BUFFERS:integer, LRU_LATCHES:integer)}
BUFFER_POOL_RECYCLE = {integer | (BUFFERS:integer, LRU_LATCHES:integer)}
[Edited by Shestakov on 04-01-2002 at 11:35 AM]