RES: log buffer size and log file syncs
Date: Fri, 27 Apr 2012 18:09:03 -0300
Today I was Reading about this topic on old, but amazing blog post from Jonathan Lewis (http://www.jlcomp.demon.co.uk/log_file_writes.html). Maybe you can find what you searching.
On OracleR Database Performance Tuning Guide documentation from 11gR2 http://docs.oracle.com/cd/E11882_01/server.112/e16638/memory.htm#PFGRF94347
7.4.1 - On most systems, sizing the log buffer larger than 1M does not provide any performance benefit. Increasing the log buffer size does not have any negative implications on performance or recoverability. It merely uses extra memory.
The official doc said "NO" for your question.
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De: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] Em nome de CRISLER, JON A
Enviada em: sexta-feira, 27 de abril de 2012 17:37 Para: oracle-l
Assunto: log buffer size and log file syncs
Has anybody run into a case where the log buffer size was too big, and negatively affected log file writes and log file sync waits ?
I have a system that ignores my parameter for 32mb log file size and sets it
to 128mb, due to the granule size. The workaround is to lower the granule
size so that I can manually set the redo log buffer lower. But I am not
sure if this will have any positive affect on log file sync times. Normal
I/O for log file writes is fast at 2-4 ms, but log file syncs are bad at 50
to 150 ms.
http://www.freelists.org/webpage/oracle-l Received on Fri Apr 27 2012 - 16:09:03 CDT