Fermin, The "checkpoint incomplete" message is a statement that your DBWR is not keeping up with the pace of redo generation. You can try to "paint over the problem" by adding redo log files. This works when you create enough redo log file space that your peak redo generation event concludes before your system needs to reuse an online redo log file.
The real root cause of this problem is that your DBWR is unable to keep up. Often, this occurs because DBWR has to compete with high I/O loads to your database files. Probably the most common cause of that high I/O load is one or more nasty SQL queries hammering on the device(s). Cary Millsap Hotsos Enterprises, Ltd. http://www.hotsos.com Upcoming events: - Hotsos Clinic 101 in Chicago, London, Reykjavik, Ottawa, Denver - Visit www.hotsos.com for schedule details... - IOUG-A Live 2003, Orlando, 10am Monday 28 April: "Oracle Operational Timing Data" -----Original Message----- Berraondo Sent: Friday, April 04, 2003 1:19 AM To: Multiple recipients of list ORACLE-L Dennis, This is our actual distribution: Datafiles belonging to data in a separate disk, name it /baandata Datafiles belonging to index in a separate disk, name it /baanindex And 3 redolog files, two of them in another two separate disks, and the third one located in the same device as the data files (/baandata). All of them are mirrored disks. Your comment makes sense, but if keeping datafiles and one of the redolog files in the same device should affect performance, then I wonder why the "cannot allocate new log, checkpoint not complete" message is affecting to the 3 redolog files and not only to the one located in that datafile device. I did not think on this. Anyway I have no more disks in which I can split the redologs... I can not wait for your comments! Regards, Fermin. -----Mensaje original----- De: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] nombre de DENNIS WILLIAMS Enviado el: jueves, 03 de abril de 2003 17:04 Para: Multiple recipients of list ORACLE-L Asunto: RE: Cannot allocate new log - checkpoint not complete Fermin - Connor's reply sparked an idea. By any chance do you have your redo logs on the same device as your data files? Dennis Williams DBA, 40%OCP, 100% DBA Lifetouch, Inc. [EMAIL PROTECTED] -----Original Message----- Sent: Thursday, April 03, 2003 5:04 AM To: Multiple recipients of list ORACLE-L Basically as the message suggests the redo cannot be recycled until the checkpoint has completed flushing out the cache. A *workaround* is to add redo log (size or number) but its really a heads-up about your I/O subsystem not being up to keep up under stress. hth connor --- Fermin Bernaus Berraondo <[EMAIL PROTECTED]> wrote: > > I think I am having problems with my redologs. > Under normal circumstances no errors arise, but if I > do a massive import of data as I was doing last > night, this is what alertSID.log shows from time to > time: > > Wed Apr 2 23:29:52 2003 > Thread 1 advanced to log sequence 557295 > Current log# 3 seq# 557295 mem# 0: > /baandata/oradata/baan/redobaan03.log > Wed Apr 2 23:31:11 2003 > Thread 1 cannot allocate new log, sequence 557296 > Checkpoint not complete > Current log# 3 seq# 557295 mem# 0: > /baandata/oradata/baan/redobaan03.log > Wed Apr 2 23:31:50 2003 > > In that exact time, everything freezes and the > database is dead until a new redolog can be used. > > I have 3 redologs 50 Mb each. I've read that the > error is because too much data is trying to get into > the redologs and all of them are full, Oracle does > not have the time to reuse a redolog and has to wait > until the redolog is ready to be reused. > > So the solution seems to make these redolog files > bigger or to create new ones. What are the side > effects of one or the other? will performance under > normal work be penalised? > > .............................................. > Fermín Bernaus Berraondo > Dpto. de Informática > SAMMIC, S.A. > [EMAIL PROTECTED] > http://www.sammic.com > Telf. +34 - 943 157 331 > Fax +34 - 943 151 276 > .............................................. > > -- > Please see the official ORACLE-L FAQ: > http://www.orafaq.net > -- > Author: Fermin Bernaus Berraondo > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 > http://www.fatcity.com > San Diego, California -- Mailing list and web > hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an > E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of > 'ListGuru') and in > the message BODY, include a line containing: UNSUB > ORACLE-L > (or the name of mailing list you want to be removed > from). You may > also send the HELP command for other information > (like subscribing). > ===== Connor McDonald web: http://www.oracledba.co.uk web: http://www.oaktable.net email: [EMAIL PROTECTED] "GIVE a man a fish and he will eat for a day. But TEACH him how to fish, and...he will sit in a boat and drink beer all day" __________________________________________________ Yahoo! Plus For a better Internet experience http://www.yahoo.co.uk/btoffer -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: =?iso-8859-1?q?Connor=20McDonald?= INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: DENNIS WILLIAMS INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Fermin Bernaus Berraondo INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Cary Millsap INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
