Log Buffer Size [message #197666] |
Thu, 12 October 2006 04:19 |
M.Shakeel Azeem
Messages: 226 Registered: September 2006
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Senior Member |
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execute the following script
SQL> @c:\sga_statistics.sql;
PL/SQL procedure successfully completed.
SQL> set serveroutput on;
SQL> /
> SGA CACHE STATISTICS
> ********************
> SQL Cache Hit rate = 99.24
> Dict Cache Hit rate = 99.67
> Buffer Cache Hit rate = 99.88
> Redo Log space requests = 1440
>
> INIT.ORA SETTING
> ****************
> Shared Pool Size = 52428800 Bytes
> DB Block Buffer = 32768 Blocks
> Log Buffer = 20971520 Bytes
>
*** HINT: Log Buffer value is rather low!
should i have to increase the size of log_buffer Because Redo Log space requests = 1440 is high?
What u'll suggest Sir?
thanx in advance
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Re: Log Buffer Size [message #197706 is a reply to message #197666] |
Thu, 12 October 2006 06:48 |
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Mahesh Rajendran
Messages: 10708 Registered: March 2002 Location: oracleDocoVille
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Senior Member Account Moderator |
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For several years now, we have been repeatedly saying in this forum
IGNORE HIT RATIOS.
Definitely, they do mean something. But it is not a measure of performance.
PLEASE SEARCH THE FORUM BEFORE POSTING.
>>should i have to increase the size of log_buffer
Is there any rationale you are applying here?
Rarely a database needs a log_buffer more than 1Mb (Optimal in many cases is 512k. But let us not generalize anything here).
Because, log buffer is flushed every 3 seconds or after every commit or when it gets full to some threshold.
So the question is ,
does the database generate/handle more than 1 Mb worth records every 3 seconds?
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