From JBECKSTROM@gcrta.org Mon, 31 Dec 2001 09:09:15 -0800 From: "Jeffrey Beckstrom" Date: Mon, 31 Dec 2001 09:09:15 -0800 Subject: RE: Redo Logs Question Message-ID: MIME-Version: 1.0 Content-Type: text/plain I try to average 1 every hour or so depending on volume.  You do have archiving on don't you.   Jeffrey BeckstromDatabase AdministratorGreater Cleveland Regional Transit Authority1240 W. 6th StreetCleveland, Ohio 44113(216) 781-4204>>> Stephen_Karniotis@compuware.com 12/31/01 11:05:20 AM >>>Tom:   File sizes of 5k are not good.  If you have the room on your server, Iwould increase that significantly.  Perhaps to 50-60m.  Log switching every90 sec. is not good.     There are many INIT.ORA parameters that control the performance of redologs.  LOG_BUFFERS or LOG_BUFFER_SIZE is one of them.  This defaults, Ibelieve, to 32k.  Increase this to over 512k.  There are many more.  Look atyour INIT.ORA settings.   Also, if you can identify the type of hardware you are running as adatabase server, we can give you some additional choices.Thank YouStephen P. KarniotisTechnical Alliance ManagerCompuware CorporationDirect:    (248) 865-4350Mobile:    (248) 408-2918Email:    Stephen.Karniotis@Compuware.comWeb:    www.compuware.com-----Original Message-----Sent:    Monday, December 31, 2001 10:20 AMTo:    Multiple recipients of list ORACLE-LSubject:    Redo Logs QuestionHere is the background of the stiuation I am facing.We are piloting a application that uses a hybred store and forward system toaggregate all of our disparate student data into one central database.Currently there are 20 schools integrated into the system with another 48 togo, those 20 schools hold about half of our 46k student population.The system allows (requires) student demographics to be entered through aweb client, while grades, attendance, health, conduct, etc. are uploadedover night.The system comes with the redo log file size set to 5k, which when the usersin the 20 pilot schools get going causes a log switch about every 90seconds.  In my limited, steep learning curve expereince, this does not seemlike a good thing.  Add to that, they cancelled the Oracle Tuning class,which I have to wait until the system is in to take now.So my questions (that the books don't really seem to want to answer):How frequently should redo log file switches occur?How large should my redo logs be?I am guessing the answer to both of these questions is, It Depends. So myquestion really is, how do I determine what the correct settings for myinstallation are?Tom-- Please see the official ORACLE-L FAQ: http://www.orafaq.com-- Author: Tom Schruefer  INET: tschruefer@mail.howard.k12.md.usFat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051San Diego, California        -- Public Internet access / Mailing Lists--------------------------------------------------------------------To REMOVE yourself from this mailing list, send an E-Mail messageto: ListGuru@fatcity.com (note EXACT spelling of 'ListGuru') and inthe message BODY, include a line containing: UNSUB ORACLE-L(or the name of mailing list you want to be removed from).  You mayalso send the HELP command for other information (like subscribing).-- Please see the official ORACLE-L FAQ: http://www.orafaq.com-- Author: Karniotis, Stephen  INET: Stephen_Karniotis@compuware.comFat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051San Diego, California        -- Public Internet access / Mailing Lists--------------------------------------------------------------------To REMOVE yourself from this mailing list, send an E-Mail messageto: ListGuru@fatcity.com (note EXACT spelling of 'ListGuru') and inthe message BODY, include a line containing: UNSUB ORACLE-L(or the name of mailing list you want to be removed from).  You mayalso send the HELP command for other information (like subscribing).