Thanks for the pointes Kristian. I definitely will be in this code shortly.
The system appeared to not be CPU bound but rather I/O bound. I need to get a test setup into a condition like at the customer first and then start doing some debugging and profiling to see where things are. -----Original Message----- From: Kristian Waagan [mailto:[email protected]] Sent: Saturday, April 23, 2016 4:22 PM To: [email protected] Subject: Re: Is there any debug logging available when a database is being recovered Den 20.04.2016 16.46, skrev Bergquist, Brett: > It took longer (and never finished) to process the recovery logs file that it > did to restore the database from the previous night from backup (that took 6 > hours to "untar") At about 14 hours, the recovery log files were not > finished processing so we had to give up and restore from backup. That > seems quite an inordinate amount of time to process the recovery log files. > Note that this was not an underpowered machine either. It was an Oracle > M5000 with 32 processors, 128G of memory, and Fibre Channel attached storage. > > I would like to start looking at this, so if anyone has any ideas where to > begin, shout them out. Hi Brett, >From what I can see, there is some logging available in debug builds using the >LogTrace-flag. I have no recollection of using it, so I cannot say how useful >the information you get from enabling it is. To try it, get the debug build and specify "derby.debug.true=LogTrace". Based on a quick scan of the code, without verifying anything, it looks like you should see when Derby switches to the next log file. There is also a log entry for the end of the redo phase. Obtaining the stack trace at various point might also give some clues if you're willing to dive into the code :) I expect this part of the code is singlethreaded, so I hope the machine can give you decent performance using a single logical CPU. Do you suspect CPU or IO to be a bottleneck? Regards, -- Kristian > > -----Original Message----- > From: Bryan Pendleton [mailto:[email protected]] > Sent: Wednesday, April 20, 2016 5:53 AM > To: [email protected] > Subject: Re: Is there any debug logging available when a database is > being recovered > >> So what would be useful would be something like: >> >> Performing database recovery >> Starting analysis pass >> 215 transactions detected to be processed Starting redo pass .... >> anything that could give some feedback Starting undo pass >> ....anything that could give some feedback >> > > I'm afraid all I can add is: yes, I completely agree, that would be extremely > useful. > > bryan > > > > Canoga Perkins > 20600 Prairie Street > Chatsworth, CA 91311 > (818) 718-6300 > > This e-mail and any attached document(s) is confidential and is intended only > for the review of the party to whom it is addressed. If you have received > this transmission in error, please notify the sender immediately and discard > the original message and any attachment(s). > Canoga Perkins 20600 Prairie Street Chatsworth, CA 91311 (818) 718-6300 This e-mail and any attached document(s) is confidential and is intended only for the review of the party to whom it is addressed. If you have received this transmission in error, please notify the sender immediately and discard the original message and any attachment(s).
