Oracle-L: RE: DB_BLOCK_CHECKING and DB_BLOCK

From: Jack C. Applewhite <japplewhite_at_inetprofit.com>
Date: Mon, 22 Apr 2002 15:08:36 -0800
Message-ID: <F001.0044BCF8.20020422150836@fatcity.com>

Beth, Dennis,

The 8.1.7 docs say that DB_Block_Checking costs 1%-10% in overhead - the 10% end for periods of intense insert/update activity - and to turn it on if you can afford it. DB_Block_Checksum costs 1%-2% and Oracle recommends turning it on always.

We've had both turned on for months (340GB 8.1.7.3.0 DB under Win2k) and not noticed any significant performance hit. We insert and index (interMedia Text) up to 280,000 documents each night, so our insert/update load is not trivial.

Having those two checks going on makes me feel more secure. We've never gotten so much as a warning, so we've not needed it. However, like any kind of insurance (e.g., backups), as long as it doesn't cost too much, aren't you glad to pay to leave it unused? ;-)

Jack

Jack C. Applewhite
Database Administrator/Developer
OCP Oracle8 DBA
iNetProfit, Inc.
Austin, Texas
www.iNetProfit.com
japplewhite_at_inetprofit.com
(512)327-9068

-----Original Message-----

Beth
Sent: Monday, April 22, 2002 3:25 PM
To: Multiple recipients of list ORACLE-L

Thanks Dennis. Its a paranoid Monday question. Actually I came across an Oracle document which suggested that they always be enabled. I was skeptical so decided to ask the real experts instead :-)

-----Original Message-----

Sent: Monday, April 22, 2002 4:03 PM
To: Multiple recipients of list ORACLE-L

Beth - Are you asking because you are experiencing a corruption problem, or because you're having a paranoid Monday? ;-) I believe the overhead is enough that you wouldn't turn them on "just because". But if you are experiencing occasional corruption, you could tolerate quite a bit of overhead. Dennis Williams
DBA
Lifetouch, Inc.
dwilliams_at_lifetouch.com

-----Original Message-----

Sent: Monday, April 22, 2002 2:20 PM
To: Multiple recipients of list ORACLE-L

Hi everybody,

I'm soliciting opinions on whether or not its a good practice to enable DB_BLOCK_CHECKING and DB_BLOCK_CHECKSUM. How much overhead is associated?

TIA, Beth

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Received on Mon Apr 22 2002 - 18:08:36 CDT

RE: DB_BLOCK_CHECKING and DB_BLOCK_CHECKSUM