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). >
