From sgraham@intertrain.net Tue, 21 Aug 2001 04:17:45 -0700
From: "Stuart Graham" <sgraham@intertrain.net>
Date: Tue, 21 Aug 2001 04:17:45 -0700
Subject: Memory Sizing
Message-ID: <F001.0037201D.20010821043524@fatcity.com>
MIME-Version: 1.0
Content-Type: text/plain



All, I have a question re Sizing of various 
memory areas in the SGA.
 
On a test box (8.1.6.0.0 NT4), I have a 
database with the following init.ora parameters...
 
db_block_buffers = 500
 
shared_pool_size = 4951040
 
large_pool_size = 614400
java_pool_size = 0
 
log_buffer = 32768
 
db_block_size = 4096
 
However, querying v$sga and v$sgastat gives 
some different results...
 
 
SQL> SELECT *  
2    FROM v$sga;
 
<FONT face="Courier New" 
size=2>NAME                      
VALUE-------------------- ----------Fixed 
Size                
70924Variable 
Size           
9756672Database Buffers        
2048000Redo 
Buffers              
77824
 
SQL> SELECT pool,  
2         SUM(bytes)  
3    FROM v$sgastat  4   GROUP BY 
pool;
 
<FONT face="Courier New" 
size=2>POOL        SUM(BYTES)----------- 
----------java pool        32768large 
pool      614400shared pool    
9091800               
2185484
 
As you can see, only my database buffers 
seem to match what was specified in the init.ora
The redo buffers are equal to 
(log_buffer*2)+ 1 block.
The shared pool bears no resemblance to 
shared_pool_size!!
 
Thanks in 
advance...