BI Trunate
- Thread starter casorohi
- Start date
dlangschied
Member
Why are you truncating your BI? It seems by your question that you are doing this often.
RealHeavyDude
Well-Known Member
You do not tell whether you have fixed BI extents or variable ones. If you have fixed BI extents, truncating the BI does not make much sense. If you have variable extents you might benefit from recovering file system space in truncating the BI.
The -G 0 [seconds to wait] parameter tells the utility not to wait and the truncation is started immediately. AFAIK the default ( 60 seconds for 9.1D IIRC ) is there as some sort of safeguard. When you stop the database and you consider all the caches ( OS, file system, controller, disk ) that play a role in this game you might get the idea that it could take some second until everything is really flushed to disk. At least, that's my understanding.
HTH, RealHeavyDude.
The -G 0 [seconds to wait] parameter tells the utility not to wait and the truncation is started immediately. AFAIK the default ( 60 seconds for 9.1D IIRC ) is there as some sort of safeguard. When you stop the database and you consider all the caches ( OS, file system, controller, disk ) that play a role in this game you might get the idea that it could take some second until everything is really flushed to disk. At least, that's my understanding.
HTH, RealHeavyDude.
MaximMonin
Member
Large BI file tells me that there are 2 problems:
1. Very Large transactions, or poor transaction control.
2. Some batches constantly writing something to DB. I have a theory that BI writer has some mark inside BI File and writes all data after this mark, then move mark forward. If there are no active transactions, bi writer can move this mark backward, and bi space will be reused. Esle bi file grows up constantly. batch pause during 1-3 minutes helps it this case. 10 Progress works a little smarter. Pauses in large transactions helps to reuse bi file space.
1. Very Large transactions, or poor transaction control.
2. Some batches constantly writing something to DB. I have a theory that BI writer has some mark inside BI File and writes all data after this mark, then move mark forward. If there are no active transactions, bi writer can move this mark backward, and bi space will be reused. Esle bi file grows up constantly. batch pause during 1-3 minutes helps it this case. 10 Progress works a little smarter. Pauses in large transactions helps to reuse bi file space.
I have two BI extents Fix at 2GB and one variable. Actually we need a separate DB copy for reporting Purpose every fortnightly. To full fill this I made a replicant DB through AI file. At the time of opening a replicant/reporting DB, AI would also be enabled. At the time of AI enabling DB goes for BI truncation, which takes to much time around 15-20 mins. I want to minimize this time.
Any work around any params that can be pass to minimize the BI truncation time.
Thanks
Any work around any params that can be pass to minimize the BI truncation time.
Thanks
RealHeavyDude
Well-Known Member
Is there any specific reason as to why you want to disable AI and enable it again - why don't you just keep it enabled?
Regards, RealHeavyDude.
Regards, RealHeavyDude.
TomBascom
Curmudgeon
The long truncate time sounds like a variation on the infamous "long redo" problem. There are no fixes to that short of an upgrade to 10.1c or better.
Well, the other fix would be to address the underlying application issues that are making the bi file so big in the first place. But people like to hear that even less than they like hearing "upgrade"...
Well, the other fix would be to address the underlying application issues that are making the bi file so big in the first place. But people like to hear that even less than they like hearing "upgrade"...
Pradeep Sh
New Member
Truncation of BI depends upon OS and your hardware also, please monitor the Truncate Process and check the CPU utilization for that, what you can do is can dedicate a CPU by psrset command of OS and see if this helps.
