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Hello1 person found this helpful
Here's my times from last night on a 100GB database, Full backup to Disk - Very fast SAN ( new ) ( My version 18.104.22.168 )
Start Time 03/21/2013:08:01:26
End Time 03/21/2013:09:03:51
So your times look OK compared to mine.
For system performance you could set the "RATE Channel Parameter" in RMAN to control this :
It would mean a longer backup time, but performance would not suffer as much.
1 person found this helpful
It takes around 4 hrs for RMAN backup. Is that normal? WE are using 4 channels.Depends on the power of your machine. I will object iif my RMAN backup will take this much time. Our 4.5 terabytes takes 3.5 hours. So it really depends upon the power of the machine.
The main issue is the system performance goes down when backup is runningIt could be b cause of I/O's, CPU , tape drive throughput etc.
Where can I look to resolve the issue.Everything is on Metalink:
RMAN Performance Troubleshooting [ID 1326686.1]
RMAN Performance Tuning Using Buffer Memory Parameters [ID 1072545.1]
RMAN Tips: Test Plan to identify correct number of channels for RMAN compressed backups optimal performance [ID 1435723.1]
Known RMAN Performance Problems [ID 247611.1]
Are you using MML or DISK ?
What you mean perfomance goes down? What happen (e.g Disk busy/ CPU 100%, Query Slow)?
Hi1 person found this helpful
Are you using Grid control then you can check the backup report details from grid. Connect the database from Grid and click- Availability - Backup Reports. Then you can see the below output.
As per the given report previous backups were run around 9-10 hrs shown as given below but the last two backups taken more time Because output rate is only 23-24 mb per second As shown below due to the data transfer rate marked in bold.
Backup Name Status Start Time Time Taken Type Output Devices Input Size Output Size Output Rate (Per Sec)
2011-02-04T22:00:12 COMPLETED Feb 4, 2011 10:01:50 PM EST *13:26:14* DB INCR SBT_TAPE 1.22T *1.14T* *24.67M*
2011-01-28T22:00:14 COMPLETED Jan 28, 2011 10:01:54 PM EST *14:21:19* DB INCR SBT_TAPE 1.22T *1.14T* *23.09M*
2011-01-21T22:00:11 COMPLETED Jan 21, 2011 10:01:39 PM EST *9:21:09* DB INCR SBT_TAPE 1.22T *1.14T* *35.43M*
2011-01-14T22:00:12 COMPLETED Jan 14, 2011 10:02:37 PM EST *9:38:55* DB INCR SBT_TAPE 1.22T *1.14T* *34.33M*
2011-01-07T22:00:09 COMPLETED Jan 7, 2011 10:01:38 PM EST *9:50:25* DB INCR SBT_TAPE 1.22T *1.14T* *33.66M*
you should be compare previous backup output rate. If it is low then you need to check which backup device(ex: Tivoli) are you using your database. if you are using any device type or backup server and then you need to check the device type or backup server health checkup. And also you need to check any jobs are scheduled other than backup that particular time.
Note: Let me know which backup type are you using.
If you are not using Grid control then you can use following.
SQL> desc rc_backup_set_details;
Name Null? Type
----------------------------------------- -------- ---------------
DB_KEY NOT NULL NUMBER
DB_NAME NOT NULL VARCHAR2(8)
BS_KEY NOT NULL NUMBER
SET_STAMP NOT NULL NUMBER
SET_COUNT NOT NULL NUMBER
PIECES NOT NULL NUMBER
Are you using incremental backup?
if you are using the INCR backup..... then are you enbled block change tracking?
Thanks for your response.
I will look into the link.
Thanks. I alreday have gone through some notes.
I will definitely look into others.
No we are not using grid control