If you run out of large pool memory, you will get an ORA-4031 error against the
large pool.  If you want to know whether you are at risk of such an error, the
best you can do is to monitor the usage at regular intervals. To do this, you
can record the current usage of the large pool at the end of each interval with
this query:

    select sum(bytes) from v$sgastat where pool = 'large pool' and name != 'free
memory';

This is not very satisfactory, because there can be transient peaks in large
pool memory usage that will go unrecorded. So the sample interval has to be
relatively short to mitigate that risk - possibly 60 seconds. Unfortunately, the
trick that is used for the reserved_pool_hwm.sql script on the Ixora web site
does not work for the large pool, because the free lists are managed
differently. So intensive monitoring is the best we can do for now.

I do have an enhancement request in with Oracle (number 883839) requesting a
mechanism to see the large pool high-water mark (possibly by including a row in
V$RESOURCE_LIMIT) but I doubt that it will happen quickly, if at all.


-----Original Message-----
Sent: Friday, 25 August 2000 1:42


How can I know I have set the right large_pool_size?