importance of the size of the Redo Log

Similar Questions

• Question about the size of the redo log buffer

  Hello
  
  I am a student in Oracle and the book I use says that having a bigger than the buffer log by default, the size is a bad idea.
  
  It sets out the reasons for this are:
  
  >
  The problem is that when a statement COMMIT is issued, part of the batch validation means to write the contents of the buffer log for redo log to disk files. This entry occurs in real time, and if it is in progress, the session that issued the VALIDATION will be suspended.
  >
  
  I understand that if the redo log buffer is too large, memory is lost and in some cases could result in disk i/o.
  
  What I'm not clear on is, the book makes it sound as if a log buffer would cause additional or IO work. I would have thought that the amount of work or IO would be substantially the same (if not identical) because writing the buffer log for redo log files is based on the postings show and not the size of the buffer itself (or its satiety).
  
  Description of the book is misleading, or did I miss something important to have a larger than necessary log buffer?
  
  Thank you for your help,
  
  John.
  
  Published by: 440bx - 11 GR 2 on August 1st, 2010 09:05 - edited for formatting of the citation

  A commit evacuates everything that in the buffer redolog for redo log files.
  A redo log buffer contains the modified data.
  But this is not just commit who empty the redolog buffer to restore the log files.
  LGWR active every time that:
  (1) a validation occurs
  (2) when the redo log is 1/3 full
  (3) every 3 seconds
  It is not always necessary that this redolog file will contain validated data.
  If there is no commit after 3 seconds, redologfile would be bound to contain uncommitted data.

  Best,
  Wissem

• SIZE OF THE REDO LOG FILE

  
  Hello

  I got an error message when I add me new group. log files I searched and found the answer on the form. Ago 4 M minimum size of 11 g R2 log file size.

  My question is why a log file size depends on DB_BLOCK_SIZE? This parameter is set to the component structures of memory that create an instance when a log file is an operating system file that depend on the version of the OS not DB_BLOCK_SIZE.

  Thank you.

  
  SQL > alter database add logfile group 4 'c:\app\asif\oradata\employee\redo04.log' size 1 m;
  alter database add logfile group 4 'c:\app\asif\oradata\employee\redo04.log' size 1 m
  *
  ERROR on line 1:
  ORA-00336: 2048 blocks the size of the log file is minimum lower than 8192 blocks

  
  SQL > show parameter db_block_size

  VALUE OF TYPE NAME
  ------------------------------------ ----------- ------------------------------
  Whole DB_BLOCK_SIZE 8192
  SQL >

  You are assuming that the redo log block size is the same as the database block size. This is not correct.

  The error indicates that 8192 is the minimum number of blocks of a redo log file. The documentation states that the minimum size is 4 M. For example, you can deduct your redo log block size is 512 bytes.

  Here's some more information about the size of redo log, the documentation block.

  Unlike the database block size, which can always be between 2 K and 32 K, redo log default files to a block size that is equal to the size of physical sector of the disk. Historically, it is usually 512 bytes (512 b).

  Some new large disks offer 4K sizes byte (4K) to increase sector efficiency improved format and ECC capabilities. Most of the Oracle database platforms are able to detect this bigger sector size. The database then automatically creates files redo log with a block size of 4 K of these discs.

• Clusterware and/or CARS on separate storage, synchronized by applying the redo logs?

  Hello Experts,

  I am doing research on architectures high availability to meet high service LEVEL requirements (> = uptime of 99.7 percent and "without loss of important data") for a client.

  I have few resources for the implementation of this architecture: two physical database servers running 11g Standard Edition (so Data Guard is not an option), Enterprise Edition is not an option because of the price. Data storage will be on a San.

  The ideal solution would be an architecture whose node redundancy (Clusterware / RAC) and redundancy of the data (as in physical Standby: application of redo logs instead of data mirroring (corrupt physical) files).

  I did research Clusterware and CARS, but they use a shared storage. I'll use a SAN for storage, but this will not prevent physical mirroring of the corrupt data files.

  Is it possible to set up a PAP/Clusterware architecture with each separate storage node, where the two databases are synchronized by applying the redo logs?

  Is it possible to instantly apply redo logs to minimize the loss of data in case of automatic failover?

  If we need more information, I'll give you a pleasure it.

  Thanks in advance,

  Peter

  A RAC cluster still need a shared storage for database files: each cluster node cannot have its own separate storage.

  You need at least a physical database server 3rd for the standby database that can function without Data Guard as long as you use you own scripts to send and apply archived redo logs or use a product like dbvisit.

  I don't think it's possible to apply again immediately without Data Guard.

• bottleneck during the passage of the redo log files.

  Hi all
  
  I'm using Oracle 11.2.0.3.
  
  The enforcement team has indicated that they are facing slow at some point.
  
  I followed the database and I found that at some passage of redo log files (not always), I am facing a slow at the application level.
  
  I have 2 son since my database is CARS, each thread has 3 groups of multiplexed redo logs the FIU, with size of 300 MB each.
  
  Is it possible to optimize the switch of the redo log files? knowing that my database is running in ARCHIVELOG mode.
  
  Kind regards

  Hello

  Yes, Oracle recommends 1 validation by 30 calls from users or less. Of course, every database is different, so this rule cannot be taken too literally, but in your case, this rule seems to apply. In any case State, 900 undertakes seconds it looks like a very large number and the need for a high number of transactions should be questioned. You should talk to your analysts/application management/enterprise architect if warranted - that is to say if the application does in fact almost 2 000 business transactions per second.

  What about DB CPU: here is a link to a blog that I wrote on this subject, it should help to better understand this number:

  http://Savvinov.com/2012/04/06/AWR-reports-interpreting-CPU-usage/

  But briefly: DB processor isn't a real event, it is simply an indication that the sessions are on CPU (or waiting for CPU) rather than wait on i/o requests or events in the database. It is not necessarily a bad thing, because the database must perform tasks and he cannot do without loading the CPU. It may indicate a problem in two cases: when the CPU usage is close to the limit of the host (OS stats section indicates that you are very far from there) or when the CPU is a % of DB time - in the latter case, this could mean that you are making too many logical reads due to inefficient plans or analysis too. In any case, this does not apply to you, because 20 percent is not very high a number.

  Other items in the list of the top 5 deserve attention, too - gc buffer busy acquire, gc current block busy, enq: TX - line lock conflict.

  To summarize, your database under a lot of stress - whether it is the legitimate workload, and if this is the case, you may need to upgrade your hardware later. There is chance that it isn't - for example a high number of runs may indicate that rather than to bulk operations database code using PL/SQL loops, which is a big performance killer. Check "Top SQL by executions" about whether or not this is the case.

  Good luck!

  Best regards
  Nikolai

• Truncate a table without removing the redo log

  Hi Experts,
  
  Could you please tell me is it possible to truncate a table without removing the Redo log. In fact, I know it is not possible, but some body asked me the same question, and I want to be sure before answering him.
  
  Help, please.
  
  Concerning
  Rajat

  >
  I'm not familiar with these tearms (Flashback or Rman backup). But I acccess DBA. Could you please tell me the procedures.
  >
  You can restore data from a backup or export.

  You cannot use FLASHBACK to recover the data unless you use GR 11, 2 and that you have prepared (using TOTAL RECALL) for this in advance.

  See Tubby response in this thread
  Flashback the truncate table is possible in 11g?

• How do I know the delay in the redo log apply on Active 11g Dataguard

  Hi all
  
  How do I know the delay in the redo log apply on Active Dataguard 11 g...
  
  Do we need to wait until the log switch occurs?
  
  Or is it recommended to provide a switch to log every 15 min, regardless of data is updated / inserted in primary school or not?
  
  Please suggest...
  
  Oracle: oracle 11g Release 2
  OS: RHEL 5.4
  
  Thank you
  
  Published by: user1687821 on February 23, 2012 12:02

  apply for time of arrival + 00 00:00:00.0 day (2) to second (1) interval February 23, 2012 03:02:16

  Here apply finish time is 'Zéro' if there are gaps in log files, this parameter shows the time it will take to resolve the discrepancy.

  apply the offset + 00 01:50:49 day (2) second (0) interval February 23, 2012 03:02:16
  transportation of shift + 00 01:50:49 day (2) second (0) interval February 23, 2012 03:02:16

  the time that redo data is not available (or) on the basis of data behind pending with the primary database.

  SQL >! date
  Thu Feb 23 03:03:34 CST 2012

  If you see your date system current and last does the end is not even a second. So probably there is no delay I would say.
  You can test by setting the timeout setting in log_archive_dest_2 (or) disable log_archive_Dest_2 for a while do two or three switches of newspaper and made attention to discrepancies between primary & eve and how does it point of view.

• Question about how Oracle manages the Redo logs

  Hello
  
  Assuming a configuration which consists of 2 redo log groups (groups A and B), each group of 2 disks (disks A1 and A2 for Group A) and B1 and B2 disks for Group B. Additionally, assume that each redo log file resides by itself in a disk storage device and that the device is dedicated to her. So in the situation described above, there are 4 discs, one for each redo log file, and each disc contains nothing other than a redo log file. Also, assume that the database is in ARCHIVELOG mode and the files from archive is stored on another different set of devices.
  
  kind of graphically:
  

      GROUP A             GROUP B
  
        A1                  B1
        A2                  B2

  The question is: when the disks that make up the Group A are filled and Oracle switches to the disks in the Group B, can the group drives to take offline, perhaps even physically removed from the system if necessary without affecting the functioning of the database? Can the archiver process temporarily delayed until the disks (which have been removed) are presented online or is the DBA have to wait until the end of the process to archive a copy of the redo log file creating in archive?
  
  Thank you for your help,
  
  John.

  Hello
  A journal of the groups fall

  To remove a group of online redo logs, you must have the ALTER DATABASE system privilege. Before you delete a line redo log group, consider the following precautions and restrictions:

  * An instance requires at least two groups of files logging online, regardless of the number of members in the groups. (A group is one or more members.)
  * You can delete a group of newspapers online redo only if it is inactive. If you need to drop the current group, first force a log switch occurs.
  * Make sure a group of online redo logs is archived (if archiving is enabled) before dropping. To see if this happens, use the view LOG V$.

  SELECT GROUP #, ARCHIVED, STATUS FROM V$ LOG;

  GROUP # ARC STATUS
  --------- --- ----------------
  1 ACTIVE YES
  2. NO CURRENT
  3 INACTIVE YES
  4 INACTIVE YES

  Delete a group of newspapers online redo with the SQL ALTER DATABASE statement with the DROP LOGFILE clause.

  The following statement drops redo log group number 3:

  ALTER DATABASE, DROP LOGFILE GROUP 3;

  When a group of online redo logs is deleted from the database, and you do not use Oracle managed files, operating system files are not removed from the disk. Instead, control of the associated database files are updated to remove members of the Group of the database structure. After deleting a group of online redo logs, make sure the drop completed successfully and then use the command of operating system appropriate to delete the dropped online redo log files.

  When you work with files managed by Oracle, the cleaning of operating system files is done automatically for you.
  Your database will not be affected as you can work with 2 files, redo log in each group, as the minimum number of redo log in a database file is two because the process LGWR (newspaper writer) writes in the redo log in a circular way. If the process crashes because you have 2 groups only if you want to remove 1 Add a third and make that the current group and remove the one you want to be offline.

  Please refer to:
  http://download.Oracle.com/docs/CD/B10500_01/server.920/a96521/onlineredo.htm#7438
  Kind regards
  Mohamed
  Oracle DBA

• How do I know if there's bottleneck in the redo logs?

  Hi all

  EBS R12.2

  11 GR 2

  OL 6.5

  We have two groups of log of size 1 GB.

  and oyour archiving logs generates 13 newspapers every hour.

  -rw - r-. 1 oraprod s/n 956896768 Jan 25 14:00 1_3372_898613761.dbf

  -rw - r-. 1 oraprod s/n 1004083200 Jan 25 14:03 1_3373_898613761.dbf

  -rw - r-. 1 oraprod s/n 928530432 Jan 25 14:10 1_3374_898613761.dbf

  -rw - r-. 1 oraprod s/n 928728576 Jan 25 14:12 1_3375_898613761.dbf

  -rw - r-. 1 oraprod s/n 967805952 Jan 25 14:20 1_3376_898613761.dbf

  -rw - r-. 1 oraprod s/n 916065792 Jan 25 14:22 1_3377_898613761.dbf

  -rw - r-. 1 oraprod s/n 951790592 Jan 25 14:30 1_3378_898613761.dbf

  -rw - r-. 1 oraprod s/n 978358272 Jan 25 14:32 1_3379_898613761.dbf

  -rw - r-. 1 oraprod s/n 974519808 Jan 25 14:40 1_3380_898613761.dbf

  -rw - r-. 1 oraprod s/n 960421376 Jan 25 14:42 1_3381_898613761.dbf

  -rw - r-. 1 oraprod s/n 917438976 Jan 25 14:49 1_3382_898613761.dbf

  -rw - r-. 1 oraprod s/n 920794624 Jan 25 14:51 1_3383_898613761.dbf

  -rw - r-. 1 oraprod s/n 920704000 Jan 25 14:59 1_3384_898613761.dbf

  I got this alert saves messages:

  Mon Jan 25 15:08:37 2016

  Filled checkpoint up to RBA [0xd3b.2.10], RCS: 5978324588151

  Mon Jan 25 15:10:57 2016

  Thread 1 cannot allot of new newspapers, sequence 3388

  Private stream flush is not complete

  Currently journal # 1, seq # 3387 mem # 0: /home/oraprod/PROD/data/log01a.dbf

  Currently journal # 1, seq # 3387 mem # 1: /home/oraprod/PROD/data/log01b.dbf

  Beginning log switch checkpoint up to RBA [0xd3c.2.10], RCS: 5978324634623

  Thread 1 Advanced for you connect to sequence 3388 (switch LGWR)

  Currently Journal # 2 seq # 3388 mem # 0: /home/oraprod/PROD/data/log02a.dbf

  Currently Journal # 2 seq # 3388 mem # 1: /home/oraprod/PROD/data/log02b.dbf

  Mon Jan 25 15:11:01 2016

  LNS: Standby redo log file selected for thread 1 sequence 3388 for destination LOG_ARCHIVE_DEST_2

  Mon Jan 25 15:11:04 2016

  Archived journal 6791 extra for each sequence 1 3387 ID thread entry 0 x 12809081 dest 1:

  Mon Jan 25 15:11:17 2016

  Filled checkpoint up to RBA [0xd3c.2.10], RCS: 5978324634623

  Mon Jan 25 15:13 2016

  Additional checkpoint up to RBA to RBA [0xd3c.1a8e82.0] [0xd3c.18d210.0], current journal line

  Mon Jan 25 15:13:04 2016

  Thread 1 cannot allot of new newspapers, sequence 3389

  Private stream flush is not complete

  Currently Journal # 2 seq # 3388 mem # 0: /home/oraprod/PROD/data/log02a.dbf

  Currently Journal # 2 seq # 3388 mem # 1: /home/oraprod/PROD/data/log02b.dbf

  Beginning log switch checkpoint up to RBA [0xd3d.2.10], RCS: 5978324673444

  Thread 1 Advanced for you connect to 3389 (switch LGWR) sequence

  Currently journal # 1, seq # 3389 mem # 0: /home/oraprod/PROD/data/log01a.dbf

  Currently journal # 1, seq # 3389 mem # 1: /home/oraprod/PROD/data/log01b.dbf

  Mon Jan 25 15:13:07 2016

  LNS: Standby redo log file selected for thread 1 sequence 3389 for destination LOG_ARCHIVE_DEST_2

  Mon Jan 25 15:13:09 2016

  Archived journal 6793 extra for each sequence 1 3388 ID thread entry 0 x 12809081 dest 1:

  Mon Jan 25 15:13:11 2016

  Filled checkpoint up to RBA [0xd3d.2.10], RCS: 5978324673444

  Is it a sign of botteneck? Users complained that each 15:00 they encounter performance degradation.

  Kind regards

  JC

  Jenna_C wrote:

  We have two groups of size 1 GB log and our archiving logs generates 13 newspapers every hour.

  Is it a sign of botteneck? Users complained that each 15:00 they encounter performance degradation.

  If your users are complaining about slow at 15:00 then look at what is happening on the system at this point in time.  Use the Active Session history, providing that you have the license, at 3 pm to see if there is a problem.  Or take snapshots of the AWR manually around 15:00 in an attempt to capture any anomaly.  Or capture instant V$ SESSION yourself manually around 15:00 and see so many sessions is pending or not.

  I have seen problems like this on shared physical infrastructure systems where the activity on a system can interfere with each other.  Attention to this kind of thing, because if it is caused by another system then you will never find the cause of the problem inside the Oracle.  Examples include backups are made at a specific time, causing large amounts of sequential disk i/o and slows down access to the drive for everything else.  Such a scenario could cause some writing redo log time to increase significantly.  Or the backup could be another system completely who shares the same disks in the same drive bay or the SAN and Bay drives or SAN is inundated by applications e/s backup.  But as it's another system, that you will not see what is happening on your Oracle database system.

  Or a virtualized with environment sharing CPU and memory where another virtual machine running a CPU intensive job and steals the Oracle system CPU capacity.  I saw the same thing with memory so - Vmware has a strange way to virtualize memory, which means it can use all of the memory on the physical hardware and run out, and then he had to intervene to release somehow little memory.  What ends up slowing things down.

  It could be a network problem - is something that the network of the floods at 15:00?  Still, backups can be a common cause of this, during the transfer of data over the network to another system.  Is there a work extracted regularly data which runs at 15:00 for example extract given OLTP to feed into a data warehouse, which is copied on the network?

  It could be many different things, causing the slowdown.  I would definitely recommend watching any expected sessions know and see if this gets worse around 15:00, or if it remains the same, in which case the problem is elsewhere.  You must also eliminate everything else - the disks, network, etc.

  Good luck

  John Brady

• Bandwidth of the network for the redo log switches

  Hi all

  I'm using Oracle 11 g R2, I want to clarify the necessary bandwidth of my primary site to the secondary site (using Oracle Data guard)

  My database is an Oracle RAC 2 nodes each node has a log size to 2 GB again. listen to this file in operation every 5 minutes. It means that I'm spending a 2 GB redo log file every 5 minutes from each node. This means that 4 GB in total every 5 minutes.

  I'm planing to set up Oracle Dataguard in maximum performance mode. Is that mean I need a link between the primary and secondary site that is able to transfer files of 2 GB + 2 GB every 5 minutes?

  I do the calculation below and need your advice:

  4 GB / (5x60s) = 13981 KByte/s

  This means that I need to link to 13981x8bites/s = 111, 848Kbit/s?

  Is the above correct? your advice please

  Kind regards

  Please check below two

  http://www.Oracle.com/au/products/database/MAA-WP-10gR2-dataguardnetworkbestpr-134557.PDF

  How to calculate bandwidth transfer network required recovery in care of data (Doc ID 736755.1)

• Create the REDO Logs after restoration of RMAN

  Version 11.2
  Platform: Solaris 10
  
  We restore the cold RMAN backup to a new server. It's a basic restore RMAN where DB name remains the same.
  
  I understand that RMAN backup online redo logs, and for good reason.
  
  We have restored our datafiles successfully. The control file still has the old entries so the query below shows old information about recovery logs
  
  -Display of the configuration of the log file the old control file data

  SYS > select * from v$logfile;         ------------> The below output shows the result of the source server
  
      GROUP# STATUS  TYPE    MEMBER                              IS_
  ---------- ------- ------- ----------------------------------- ---
           1         ONLINE  /DATAM/DB/oradata/slmps/redo1.log      NO
           2         ONLINE  /DATAM/DB/oradata/slmps/redo2.log      NO
           3         ONLINE  /DATAM/DB/oradata/slmps/redo3.log      NO

  I have to use ALTER DATABASE RENAME FILE command as below to update the control file.

  alter database rename file '/DATAM/DB/oradata/slmps/redo1.log' to '/data/oradata/slmps/slmps_log01.dbf' ;
  alter database rename file '/DATAM/DB/oradata/slmps/redo2.log' to '/data/oradata/slmps/slmps_log02.dbf' ;
  alter database rename file '/DATAM/DB/oradata/slmps/redo3.log' to '/data/oradata/slmps/slmps_log03.dbf' ;  

  Currently, in the new server, at the level of the BONE there is no physical file above to
  

  /data/oradata/slmps

  I need to create physically redo new logs using the command or the command ALTER DATABASE RENAME above key create a physical file at the level of the BONE?

  Salvation in spiral,

  Surely, RMAN will search for redo logs when RECOVER is issued.

  When you issue the command RECOVER after restore, RMAN does not check online redo logs. During RECOVERY, RMAN will try to apply the archivelogs or incremental L1 if it has been saved on the source server. RMAN Backup restorations online redo logs or never.

  Here OP tries to restore the backup from the cold to a new server. In this case the RECOVER command is not necessary. The example of the Oracle doc you mentioned should do a restore, recovery of a backup hot. In this case, during the RESTORATION, RMAN will try to apply archivelogs or L1 of the incremental backups.

  In both cases (cold backup restore or restore, recover from Hot Backup), it is the

  alter database open resetlogs
  

  command that will create the online redo log, so it is absent in the location specified by the control file. Because it is a restoration to a new server, recovery logs is missing because it has not been restored (because it has not been saved)

• How to change the location of the redo log files... ?

  I want all my redo log files to be created in \u10 instead of/U01 current?
  How to do? NOARCHIVELOG mode database on Oracle 10 g R2.
  Thank you
  Smirh

  user517525 wrote:
  Thank you
  Smirh

  [Move Redo Log members | http://download.oracle.com/docs/cd/B19306_01/server.102/b14231/onlineredo.htm#sthref951]

• At the time to rename the redo log file, I got the following error.

  SQL > host moves D:\oracle\product\10.2.0\oradata\test\redo02.log D:\oracle\produc
  t\10.2.0\oradata\test\re.log
  The process cannot access the file because it is being used by another process.

  This isn't a surprise if you do not rename the file also with SQL statements before the move in the OS layer. Did you?

  Add above: If you just want to get a group of newspapers moved to another directory, the right way to do that would be
  (1) to create the new group to the destination of your choice
  (2) the old Group drop
  (3) delete the old OS layer group

  This is done online, while the instance continues to run in the OPEN State.

  Kind regards
  Uwe Hesse

  http://uhesse.WordPress.com

  Published by: Uwe Hesse on 29.07.2010 12:08

• What are the causes of archivedlog of size to be different from the size of the online redo log?

  11 GR 2 on RHEL 6.2

  4 GB is our size of Redo Log online.

  SQL > select bytes/1024/1024/1024 GB of log v$.

  GB

  ----------

  4

  4

  4

  4

  But the archive logs are 3.55 GB in size instead of 4 GB. Some of the archivelogs that are smaller than 3.55 below must be caused by

  Archive log backup RMAN offers jobs at 10:00, 16:00 and 22:00 that initiates log switching (I guess)

  SQL > select (blocks * block_size/1024/1024/1024) GB of v$ archived_log where status = 'A ';

  GB

  ----------

  3.55978966

  3.31046581

  3.55826092

  3.55963707

  1.39474106

  3.561553

  3.55736685

  3.55881786

  .135155678

  3.55546999

  .054887295

  1.88027525

  .078295708

  1.97425985

  3.55703735

  3.55765438

  .421986103

  3.55839968

  < snipped >

  It has something to do with the parameter FAST_START_MTTR_TARGET ? It is set to zero in this PB anyway.

  SQL > show parameter mtt

  VALUE OF TYPE NAME

  ------------------------------------ ----------- ------------------------------

  fast_start_mttr_target integer 0

  SQL >

  He could carry on public discussions and private discussions as Jonathan Lewis points out in the other discussion that Mihael provides a link to.

  It could concern the parameter archive_lag_target

  It could be the result of the BACKUP of RMAN commands

  It may be a programmed script / who commands ALTER SYSTEM ARCHIVE LOG of employment issues.

  Oracle can create an archivelog that is smaller than the redo log, if it isn't a switch or command before archive the redo log is full.

  Hemant K Collette

• How to create Redo Log as a good way to avoid the problem of performance

  Hi Experts,

  I work in the following environment.

  OS - Windows server 2012

  version - 11.2.0.1.0

  Server: production server

  1 to 10 of each month, we have huge process. Like many DML and ddl involve.

  I've implemented the RMAN also.

  My Alerts log entry is as below,

  Kills Sep 08 17:05:34 2015

  Thread 1 cannot allot of new newspapers, 88278 sequence

  Private stream flush is not complete

  Currently journal # 1, seq # 88277 mem # 0: D:\APP\ADMINISTRATOR\ORADATA\AWSPROCESS\REDO01. JOURNAL

  Thread 1 Advanced to record the sequence 88278 (switch LGWR)

  Currently Journal # 2 seq # 88278 mem # 0: D:\APP\ADMINISTRATOR\ORADATA\AWSPROCESS\REDO02. JOURNAL

  Kills Sep 08 17:05:38 2015

  Archived journal 81073 extra for each sequence 1 88277 0x38b3fdf6 dest ID thread entry 1:

  Kills Sep 08 17:05:52 2015

  Thread 1 cannot allot of new newspapers, sequence 88279

  Checkpoint is not complete

  Currently Journal # 2 seq # 88278 mem # 0: D:\APP\ADMINISTRATOR\ORADATA\AWSPROCESS\REDO02. JOURNAL

  Thread 1 Advanced to record the sequence 88279 (switch LGWR)

  Currently Journal # 3 seq # 88279 mem # 0: D:\APP\ADMINISTRATOR\ORADATA\AWSPROCESS\REDO03. JOURNAL

  Kills Sep 08 17:05:58 2015

  Archived journal 81074 extra for each sequence 1 88278 0x38b3fdf6 dest ID thread entry 1:

  Kills Sep 08 17:06:16 2015

  Thread 1 cannot allot of new newspapers, sequence 88280

  Checkpoint is not complete

  When I check in the internet I found a few points and need clarity also by the following.

  -It is recommended that this switch Redo log 5 times maximum per hour, but I have this time of maximum peak about 100 redo log changes occur.

  -It is recommended to have the large size of the Redo log. But I have 3 Group of redo and each size is 50 MB by default.

  -My group of Redo log not multiplexed and it by default with each group have only a single Member

  Group 1 - D:\APP\ADMINISTRATOR\ORADATA\AWSPROCESS\REDO01. JOURNAL

  Group 2 - D:\APP\ADMINISTRATOR\ORADATA\AWSPROCESS\REDO02. JOURNAL

  Group 3 - D:\APP\ADMINISTRATOR\ORADATA\AWSPROCESS\REDO03. JOURNAL

  And advised by experts with add that again group will give more performance in the other location. Is it mean that I need to add the Redo log as a different group, player or Redo Log itself I need to replace the other location.

  Say in the end, My Live server works with the location and size of restore default. I'm trying to create a better way and get all confused

  How to do it perfectly.

  Experts, please share your comments to my environment to log redo instance as better through your comment or recommended weblink based on my above needs, or a document.

  Thanks in advance, if you need more information to help me, then ask me, I'll share you.

  Hello

  You can't resize an existing redo log group.

  You will need to create 3 new redo log groups and drop old log redo (with 200 MB size) groups.

  Here you can find a good explanation: DBA for Oracle tips Archives