<s>
In	O
the	O
database	B-Application
management	I-Application
systems	I-Application
developed	O
by	O
the	B-Application
Oracle	I-Application
Corporation	I-Application
,	O
the	O
System	B-Application
Global	I-Application
Area	I-Application
(	O
SGA	O
)	O
forms	O
the	O
part	O
of	O
the	O
system	O
memory	O
(	O
RAM	B-Architecture
)	O
shared	O
by	O
all	O
the	O
processes	O
belonging	O
to	O
a	O
single	O
Oracle	B-General_Concept
database	I-General_Concept
instance	O
.	O
</s>
<s>
shared	O
pool	O
:	O
holds	O
the	O
dictionary	O
or	O
row	O
cache	B-General_Concept
,	O
the	O
library	O
cache	B-General_Concept
,	O
cursor	O
definitions	O
and	O
shared	O
SQL	O
.	O
</s>
<s>
Java	B-Language
pool	O
:	O
holds	O
information	O
for	O
parsing	O
Java	B-Language
statements	O
.	O
</s>
<s>
From	O
Oracle	B-General_Concept
Database	I-General_Concept
version	O
10g	O
,	O
Automatic	O
Memory	O
Management	O
(	O
AMM	O
)	O
allows	O
simplified	O
and	O
dynamic	O
configuration	O
of	O
the	O
SGA	O
.	O
</s>
<s>
In	O
the	O
Oracle	B-General_Concept
DBMS	I-General_Concept
,	O
the	O
Oracle	B-General_Concept
server	O
allocates	O
the	O
system	B-Application
global	I-Application
area	I-Application
(	O
SGA	O
)	O
in	O
granule	B-Application
units	O
at	O
the	O
time	O
of	O
instance	O
startup	O
.	O
</s>
<s>
During	O
the	O
startup	O
,	O
each	O
component	O
acquires	O
as	O
many	O
granules	B-Application
as	O
it	O
requires	O
.	O
</s>
<s>
The	O
SGA	O
can	O
be	O
said	O
to	O
consist	O
of	O
linked	O
granules	B-Application
.	O
</s>
<s>
The	O
granule	B-Application
size	O
depends	O
on	O
the	O
database	O
version	O
and	O
sometimes	O
on	O
the	O
operating	O
system	O
.	O
</s>
<s>
In	O
Oracle	B-General_Concept
9i	O
and	O
earlier	O
,	O
it	O
is	O
4	O
MB	O
if	O
the	O
SGA	O
size	O
is	O
less	O
than	O
128	O
MB	O
,	O
and	O
16	O
MB	O
otherwise	O
.	O
</s>
<s>
There	O
must	O
be	O
at	O
least	O
3	O
granules	B-Application
in	O
the	O
SGA	O
:	O
one	O
for	O
the	O
Database	O
Buffer	O
Cache	B-General_Concept
,	O
one	O
for	O
the	O
Shared	O
Pool	O
Area	O
and	O
one	O
for	O
the	O
Redo	B-Application
Log	I-Application
Buffer	O
.	O
</s>
<s>
It	O
is	O
possible	O
to	O
retrieve	O
information	O
about	O
the	O
current	O
granule	B-Application
size	O
at	O
any	O
time	O
by	O
querying	O
the	O
dynamic	O
view	O
V$SGAINFO	O
.	O
</s>
