Re: Expand SGA but performance slow down?

Expanding the SGA only speeds things up if you are memory-bound. In this case it sounds like you were not, and are taking a few extra seconds to allocate the extra buffers the first time you run a query.

Try running a large query several times under your original setup and the new setup, and you will see the difference.

hth -

Regards,
jh

Violin (violin.hsiao_at_mail.pouchen.com.tw) wrote:
: Hello,
: 2 days ago I changed the init.ora and startup again.
: In init.ora,I changed the:
: db_block_buffers = 200 --> 6400
: shared_pool_size = 3500000 --> 10000000
: log_buffer = 8192 --> 245760
: processes = 50 -->100

: After startup database again,the SGA allocated successfully.
: Database Buffers = 400K --> 12800KBytes
: Fixed Size=35K --> 31K
: Redo Buffers=8K --> 240K
: Variable Size=6887K --> 12526K

: When I do the same SQL for a large amount of rows(about 37,000) for
: select and insert statement,
: Before changed SGA,the statement takes 5 seconds to complete.
: After changed SGA,it takes 17 seconds to complete.
: Why???
: Isn't the SGA more large more better?
: If you know why,please tell me.
: Please Cc to : violin.hsiao_at_mail.pouchen.com.tw,Thank you :)

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Jared Hecker	| HWA Inc. - Oracle architecture and Administration
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