Log size and log buffer parameter

[clinton]

Hi

What's the difference between specifying the
log file in the create database script
like in the example below:

logfile
group 1 (‘\redo_01.log’) size 5M
group 2 (‘\redo_02.log’) size 5M
group 3 (‘\redo_03.log’) size 5M

and specifying LOG BUFFER parameter in the initSID.ora file
like specified below

log_buffer = 5242880

[davey23uk]

LOG_BUFFER specifies the amount of memory, in bytes, that Oracle uses when buffering redo entries to a redo log file.

Redo log entries contain a record of the changes that have been made to the database block buffers. The LGWR process writes redo log entries from the log buffer to a redo log file.

In general, larger values for LOG_BUFFER reduce redo log file I/O, particularly if transactions are long or numerous. In a busy system, a value 65536 or higher is reasonable.

(robbed from Metalink)

In short, log_buffer is in memory your redo logs are physically on disk