Confusion of the control point

Similar Questions

• Confused about "additional control Points.

  Hello

  I'm confused about this sentence from database Concepts 11g Release 2 (11.2)

  Additional control points

  An additional control point is a type of thread control point in part intended to avoid writing a large number of blocks online redo log switches. DBWn checks at least every three seconds to determine if he has to do. When DBWn written stamps Sales, it advances the position of the control point, causing CKPT write the position of the control point to the file control, but not for data file headers.

  I thought that a checkpoint is written datafileheader and controlfile, this happens for example after a switch logfile - right?

  So, why not in the case of additional control point? For best performance?

  Additional control points to reduce the time to recover, as more data is committed to the files of data, right?

  Concerning
  Christian

  efa78257-b5f4-4db1-8222-007be18d15aa wrote:

  Hello

  I'm confused about this sentence from database Concepts 11g Release 2 (11.2)

  Additional control points

  An additional control point is a type of thread control point in part intended to avoid writing a large number of blocks online redo log switches. DBWn checks at least every three seconds to determine if he has to do. When DBWn writes buffers of Sales, it advances the position of the control point, causing CKPT write the position of the control point to the file control, but not for data file headers.

  I thought that a checkpoint is written datafileheader and controlfile, this happens for example after a switch logfile - right?

  So, why not in the case of additional control point? For best performance?

  Additional control points to reduce the time to recover, as more data is committed to the files of data, right?

  Concerning
  Christian

  There are many types of control points. One that will be updated on the headers of data files would be a complete control and would be applicable to the entire base. The additional control point is induced to keep on enhanching a counter that would ensure that only certain limited stamp Sales would be recovering. That's why a moment of the additional control point, data file headers are not being updated. Control file is probably updated with a "pointer to disk" which mentions the point up to which the dirty buffers are written in files (from the buffer cache) data and where to start the recovery, if necessary. Log file switch will cause a thread control point which, for one instance, would be considered a Global checkpoint only. The additional control point would be for various other reasons such as setting a value for the parameter Fast_Start_Mttr_Target etc.

  HTH

  Aman...

• Oracle concepts: Clarity on the control points required

  First of all, I should mention my understanding, and then I'll raise my doubts/queries:
  
  I think I know just enough of what are the points of control and their purpose; in order to validate and to have a deeper understanding, I was going through section "Importance of control points for example recovery ' chapter 'Instance of Oracle database' of ' 11 g Release 2 Oracle® database Concepts'.»
  -Oracle link Docs
  http://docs.Oracle.com/CD/E11882_01/server.112/e25789/startup.htm
  
  Now I need some clarification on the mentioned content there.
  
  I knew that control points are used to ensure that the control file and data files are synchronized and and it is a point where recovery instance is required, doc Oracle he mentions as a control point position.
  
  First question:
  I see many types of checkpoints mentioned here as put on checkpoints, Tablespace and data files checkpoints and additional checkpoints, I tried to get that said, can anyone make it a little clearer to me in simple terms?
  
  Second question:
  In the Oracle RAC environment, there are several threads to redo (one for each instance), how recovery Instance that happens? It is not clear to me, I want to say how serialization between multiple threads to roll forward to retrieve one or more has no instances?
  
  Kind regards
  Ankit Rouault

  NVO wrote:

  First question:
  I see that many types of checkpoints mentioned here as put on checkpoints, Tablespace and control points data files & additional checkpoints, I tried to get that said, can anyone make it a little clearer to me in simple terms?

  The term "checkpoint" has changed meaning over time. The original meaning was close to your description - a control point has allowed Oracle to determine that all blocks of data changed before a specific point in time (SNA) was written on the disc - however there are has reasons why Oracle might want to make sure that a specific blocks of data modified subset had been written on the disc and that's why the checkpoint term has expanded to cover the options such as a checkpoint of tablespace, or a checkpoint of object reuse. For example - if you truncate an object, then Oracle must copy everything puts in buffer for just that object on the disk before making the data dictionary and the space of management changes which perform the truncate (where the control point"reuse of objects '").

  Second question:
  In the Oracle RAC environment, there are several threads to redo (one for each instance), how recovery Instance that happens? It is not clear to me, I want to say how serialization between multiple threads to roll forward to retrieve one or more has no instances?

  All active instances in a RAC system will be constantly chatting to each other on the network and via the control lead - as soon as any instance think of another instance has failed, it will try to acquire exclusive global "recovery lock" - on the top of my head, I think it's the lock of the IR. When he arrives this lock, all other cases knows that there is a body controlling a recovery. Indeed the instance that got the blocking takes on the identity of the instance failed to recover through its newspapers online redo - obviously the process are much more complex than that, but it's probably a good starting point for an answer to your question.

  Concerning
  Jonathan Lewis

• No pen or the control points lightroom radial filter 5

  No pen or the control points lightroom radial filter 5

  Press H

• When I try to access the windows Defender it says operation has been cancelled due to restrictions in effect on this computor. I think I uninstalled the control point

  I went to the windows Defender to change visual effects to take into account what was best for the performance. Now when I try to access windows Defender it says this operation has been cancelled due to restrictions in effect on this computer. Contact the system administrator. I tried to do a system restore, and looks that I uninstalled windows defender control point. What should I do

  Hello gailhorne,

  Do you have any antivirus software installed?  Please visit the link below and let us know the status.

  running windows Defender but receive error message that this operation has been cancelled the restrictions in effect on this computer

  http://answers.Microsoft.com/en-us/protect/Forum/protect_scanning/trying-to-run-Windows-Defender-but-get-error/6969e099-6c42-47B5-ADC5-18804bce3cb6

• Redo log switch always calls the control point?

  Hello

  Is a log switch redo always calls process checkpoint?

  I have a database of test on which nothing is not running, but when I switch the redo log file, so it takes time to make the State of redo log active to INACTIVE.

  But when I change check system; the State immediately changes from ACTIVE to INACTIVE.

  Gives me a feeling that the redo log switch, it is not mandatory for the checkpoint occurs.

  DB version is 11.2.0.1

  Comment of nicely.

  A 11.2.0.4 alert after log is 3 'alter system switch logfile' in a line:

  ALTER SYSTEM SET log_checkpoints_to_alert = TRUE SCOPE = BOTH;

  Wed Apr 16 22:17:09 2014

  Beginning log switch checkpoint up to RBA [0xd8.2.10], SNA: 12670277595657 *.

  Thread 1 Advanced to save the 216 (switch LGWR) sequence

  Currently Journal # 3 seq # 216 mem # 0: /u01/app/oracle/oradata/TEST/onlinelog/o1_mf_3_938s43lb_.log

  Currently Journal # 3 seq # 216 mem # 1: /u01/app/oracle/fast_recovery_area/TEST/onlinelog/o1_mf_3_938s49xz_.log

  Wed Apr 16 22:17:25 2014

  Beginning log switch checkpoint up to RBA [0xd9.2.10], SNA: 12670277595726 *.

  Thread 1 Advanced to record the sequence 217 (switch LGWR)

  Currently journal # 1, seq # 217 mem # 0: /u01/app/oracle/oradata/TEST/onlinelog/o1_mf_1_938s3lbv_.log

  Currently journal # 1, seq # 217 mem # 1: /u01/app/oracle/fast_recovery_area/TEST/onlinelog/o1_mf_1_938s3nmc_.log

  Wed Apr 16 22:17:36 2014

  Thread 1 cannot allot of new newspapers, sequence 218

  Checkpoint is not complete

  Currently journal # 1, seq # 217 mem # 0: /u01/app/oracle/oradata/TEST/onlinelog/o1_mf_1_938s3lbv_.log

  Currently journal # 1, seq # 217 mem # 1: /u01/app/oracle/fast_recovery_area/TEST/onlinelog/o1_mf_1_938s3nmc_.log

  Wed Apr 16 22:17:40 2014

  Checkpoint completed up to [0xd8.2.10], YVERT RBA: 12670277595657 +++

  Beginning log switch checkpoint up to RBA [0xda.2.10], SNA: 12670277596242 *.

  Thread 1 Advanced to record the sequence of 218 (switch LGWR)

  Notice how we have lines (marked *) what does "beginning log switch checkpoint."

  However, note that control points are not "emergency" until we have a problem with "checkpoint is not complete", and the first control point in the bucket fill in only some time after the second control point in the dumpster.  Log switch checkpoint he still 'place' (or, at least, its necessity is noticed) - but it is not the urgent case where it used to be in early versions of Oracle.

  Concerning

  Jonathan Lewis

• Flatten the control point handles

  Hi Expert Adobe and types of charitable :-)

  I work on a certain type at the moment and wanted to use the anchor points and handles control as an effect in the final work.

  I tried to use 'See the Bounding Box' after flattening of the text and made a screenshot to Photoshop.

  Using this method the anchor points are visible, but unless you select the particular anchor with the direct Selection tool,
  control handles are never visible. I must also import to Illustrator and use the tracing, which I do not think that would work very well...

  Is it possible to easily convert Illustrator guide marks and control handles at work?

  All greatefully suggestions appreciated!

  Thanks much :-) J

  I have good was at work

  The script is a bit too long to comfortably inside this message, and it seems you still cannot attach files, so download it from my site: www.jongware.com/binaries/drawArtHandles.zip

  Select one or more objects, and it will make a layer called 'Art Visible' (or use one that already exists) and all handles, anchors, bounding and whatnot boxes press. He "supports" (i.e., the prints handles) text, groups and simple traces. Gets all the rest - bitmaps, symbols, graphics... - the I am ignorant you treatment.

  (I noticed a small bug: sometimes Illustrator won't cooperate and refuses to set the color for the frame of the "bounding box".) What is happening with this? I don't know - everything else seems to be in order).

  Here's what it looks like - don't like, you have now all handles selected at the same time?

  

• Issues related to the control point.

  Hello
  
  I have a doubt, checkpoint,
  
  Writing database writes data to stop data to the control files.
  
  In my view, the database writer writes only stamps Sales (which are commited buffers) in the data files. Can someone delete this
  
  
  Thnks

  user10745179 wrote:
  Hello

  I have a doubt, checkpoint,

  Writing database writes data to stop data to the control files.

  In my view, the database writer writes only stamps Sales (which are commited buffers) in the data files. Can someone delete this

  Thnks

  Yes, database writes the uncommitted to the data files. In case you long uncommitted transaction, this would mean that you have a lot of data not validated in the database buffer cache. There might come a time where all the data of the dbc is not validated, if more data must be written in DCB, no own stamp will be available to write and the cause of crashing instance. In such a situation, the dirty unvalidated data are also flushed to the data files but is not accessible until the transaction is complete, once the changes take place and other users will get the changed data.
  Kind regards
  Blabla

• The merger between the two images with the control points? Novice request

  Hi all

  I've seen a tutorial that describes exactly what I want to achieve, but can't for the life of me remember of it called or how to do it.

  Basically, I have two images of the map I want to put in a short film. During the transition between the images, instead of simply melted into a single image I want that they "sink" in the following image.

  The tutorial I've seen used Premiere Pro and "checkpoints" that match between the two images showing where things moved too.

  I am barking the wrong tree? I will reply cheerfully questions in an attempt to better describe this. I apologize for the vagueness of the topic.

  Tom

  For a quick and dirty overview using the track Matte Keying, see this glance for this purpose: https://vimeo.com/user17132571/review/69330020/8f4fc79c86

  Hunt

• Adjustment of the control point

  Hi all
  
  Then any body tell me the significance of the parameter ARCHIVE_LAG_TARGET and FAST_START_MTTR_TARGET. I mean what are the scenarios in which we will use them.
  
  If any doc available please give me the link.

  Mr President.

  For the 10g database, you can find pretty much everything from the link below.

  http://www.Oracle.com/pls/db102/homepage

• Ground control point and of the CNS by using process DBWr and LOGWr?

  What control point has to do with the log writer process I don't get exactly?...
  
  As I fire 1 query updated and apparently it will generate some redo blocks which in turn will come to my redo log files now in this cycle where the control point will occur and why?
  
  (1) my update query
  (2) lock
  (3) generate redo
  (4) generate cancel
  5 blocks) are changed, but they are still in the redo log buffer...
  
  Now this block finally comes to redo logs in all this way to check off pointing place and why?
  
  control point takes place also however is flushed to the data files the same reason why?
  
  Same manner around the same question the checkpointing should do with the DBWr process as I'm unclear...
  
  -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  Apart from this overview of the SNA is generated when the user launches period... and we can say YVERT can be used to identify whether or not the transaction is validated. ?
  So what is the reason for the SNA update in the control file... Can b to get the last transaction committed... ??
  
  Sorry a thread with questions so much... but this all things create a blurry image, I want to clearly say thnx for your help in advance...
  I've read the documentation, but they did not mention deep for recovery... ??
  
  
  
  Thank you
  Philippe
  
  Published by: 851733 on April 12, 2011 07:57

  And you the chance to read the guide to the Concepts and the book, Expert, alone that I proposed to read? I guess no, no? You mean, you have to read two books for sure because it would take a lot of time before you would get things correctly.

  YVERT is a like a timestamp which oracle maintain separate trasactions of time?

  Evil. CPN is with each operation, whether a DML, select, DDL, whatever it is. It's time, that's all. Validation of a transaction would be just another event that will be mapped to the SCN generated right here.

  Checkpoint is a SNA during which we emptied all Sales buffers to disk?

  Have you read in my last response I mentioned CPN is to read-consitancy and checkpoint is for the recvoery? So, how you said that this point of control is nothing other than RCS? See the definition of the Concepts guide,

  A data structure that marks the position of the control point, which is the RCS in the thread again where instance recovery should begin. Control points are recorded in the control file and each file header data and are a crucial part of the recovery.

  So assuming that the roll forward flow is as below,

  Begin - Checkpoint - end

  The point where the word Checkpoint is mentioned, is the place where begins the recovery.

  Control files and headers of the data files are updated with the last control point (now this checkpoint is the last SNA by what buffer cache is empty so that we can know up to what our data files are updated).

  Read the above, given the definition of the control point.

  Buffers are marked with YVERT?

  Don't know what you mean by this statement?

  Tell you what, read the guide concepts and Experts, by Tom Kyte to understand these things in a way much better. Besides, if you can organize, attend the session for workshop-1 or 2 modules of Oracle University, where the instructor would release these questions into a long discussion, very strongly suggested that with the above mentioned books.

  Aman...

• Control point for endpoint connect is compatible with Windows 8.1?

  Original title: CheckPoint endpoint connect

  Hello

  I'll do the upgrade of Windows 8 Pro for Windows Pro 8.1.

  By choosing the upgrade path that allows me to keep all the files, settings and applications, it shows that the only application that I have to uninstall will be Checkpoint Endpoint Connect (which currently runs under Windows 8 Pro).

  At all known installation CheckPoint EndPoint Connect on Windows Pro 8.1 and installed successfully?

  Thanks for the reply.

  I've went ahead with the installation of Windows RTM 8.1 and took the risk that Checkpoint would not be compatible.

  I was able to uninstall Checkpoint, as part of the upgrade of Windows 8.1 window and subsequently install Checkpoint endpoint connect successfully.

  Therefore, I am happy to say that for our Organization and our version of the control point, it is looking like it is fully compatible with Windows 8.1.

• Table of control point missing Golden gate

  Hello gurus,
  
  I'm trying to implement direct replication with Golden Gate, but I can't create the control point table.
  
  
  GGSCI (26) > ADD CHECKPOINTTABLE
  ERROR: Missing checkpoint table specification.
  
  GGSCI (q) 27 > ADD REPLICAT rep1, EXTTRAIL/t01/software/gg2/dirdat/rt
  ERROR: No control points table specified to add REPLICAT.
  
  
  GGSCI (28) > ADD CHECKPOINTTABLE
  ERROR: Missing checkpoint table specification.
  
  GGSCI (qcdvap1031.gnet.qc.bell.ca) 29 > edit. / GLOBALS
  ERROR: Invalid command.
  
  GGSCI (30) > edit params. / GLOBALS
  GGSCHEMA GGS_OWNER
  CHECKPOINTTABLE GGS_OWNER. CHKPTAB
  
  
  GGSCI (q) 31 > add CHECKPOINTTABLE GGS_OWNER. CHKPTAB
  
  Managed to create the table GGS_OWNER of control point. CHKPTAB.
  
  GGSCI (32) > ADD REPLICAT rep1, EXTTRAIL/t01/software/gg2/dirdat/rt
  ERROR: No control points table specified to add REPLICAT.
  
  Don't know what I'm missing here, can someone please help?
  
  Thank you very much

  Specify the control point table in the global file is every time that you restart your replica he get the overall point check table form file.
  But while adding you must always specify tablename.

  hope that make sense

• "physical, no written control point" is low, but increase in roll forward does not help.

  We have a busy database, the physical write is so high that we want to reduce the physical writing. The statspack, we could see "physical writes non checkpoint" is low in comparison with 'physical writing', so I think the physical write results from control point is high, then I increased the size of Redo from 2 G to 4 G (now the command to log every 4 minutes). I hope that this may reduce the physical writing, but the fact is that the roll increased forward is powerless.

  Statistic                                      Total     per Second    per Trans
  --------------------------------- ------------------ -------------- ------------
  physical writes                            8,298,681        9,210.5        249.8
  physical writes non checkpoint             3,229,321        3,584.2         97.2

  We use the oracle 10.2.0.3 on solaris 10, checkpoint-related parameters are

  fast_start_io_target                          0                  
  fast_start_mttr_target                        0                  
  log_checkpoint_interval                       5000000            
  log_checkpoint_timeout                        0     

  Thank you
  
  Published by: user646745 on August 18, 2009 01:24

  FAST_START_MTTR_TARGET is set to 0

  Make sure that you explicitly defined FAST_START_MTTR_TARGET on 0.
  If you have not set it, a "show"parameter will be enabled see the value 0, but the automatic setting of the control point will be . (See Note MetaLink #265831.1)

  If the size of redo is 4G, we will have two control points for each 4G...

  Yes, there will be one for the log_checkpoint_interval and the other for the control of log file.

• Question of control point

  Hello
  IM using TimesTen Release 7.0.4.3.0
  
  Here's my entry sysodbc.ini
  =====================
  
  [DG_222221]
  Driver=/opt/TimesTen/Kodiak/lib/libtten.so
  Data store = / DG/Datastore/DG_222221
  PermSize = 200
  TempSize = 50
  DurableCommits = 0
  AutoCreate = 0
  OverWrite = 0
  LockWait = 5
  LogBuffSize = 10240
  LogFileSize = 20
  Isolation = 1
  LockLevel = 0
  Authenticate = 1
  SMPOptLevel = 1
  GroupRestrict = kodiakgroup
  Connections = 840
  DatabaseCharacterSet = TIMESTEN8
  TypeMode = 1
  CkptFrequency = 60
  CkptLogVolume = 0
  
  Please see that frequency of control point is 60 seconds.
  
  Here, the problem is when I change the timestamp of my system to another date (date in advance, say original date is Mon May 11 13:17:22 2009 IST, I change to May 25 and then come back may 11); After that this checkpoint only will be not for the data store even if the checpoint process can be seen in the output of ttStatus. Control point is not moving any further even if do a restart of the service timesten.
  
  Can I know what could be the reason?
  
  Concerning
  Pratheej

  In general, most of the software will tolerate the system clock is put forward in time (there are exceptions), and most of the software (again there are exceptions) will have problems if the clock is set backwards in time, especially by such an amount. TimesTen, like many other software components (especially databases) use internal timestamps and so forth to follow things like when the control points is produced and so on. Change the time as this will of course cause problems and is therefore not supported. Basically, don't do it!

  To obtain the control points running on that store of data again, you need to you follow these steps:

  1. the data store any export to a flat file using ttMigrate - c

  2. remove the data store (using ttDestroy).

  3 re - create and re - load the migration dump data store using ttMigrate - r.

  Chris