Hi, I am confused with exchange 2003 checkpoint depth. Actually, checkpoint depth is 20 MB per SG but.... checkpoint depth is 1024 uncommited log files per SG (harcoded) as well. I need to know if checkpoint depth is 20 MB then I understand exchange can bear maximum 4 uncommited log files before getting dismount (condition: where DB locks due to backup etc.) Where this 1024 uncommited log files concept comes in picture if checkpoint depth is 20MB (4 log files). Can someone please explain this? Thanks,

I believe Michael Meanderings answered it here http://theessentialexchange.com/blogs/michael/archive/2008/04/28/ESE-Checkpoint-Depth.aspxRegards zizebra http://auction.joyoustimes.net

The article only says that : The "checkpoint depth" is how many checkpointed logfiles must be processed before the ESE database is current with the transaction log files. This article does not clear what I have asked.

Hi It is very interesting topic. I remember rich explains it at the beginning of 2011. The 20MB value is the maximum amount of data that the ESE can write to logs before it writes it to the database. But transactions can span more than 20MB and on a busy server it doesn't take long to accumulate 20MB of data. So you may have many log files with uncommitted transactions, but you won't have more then four log files worth of data that hasn't been written to the database. But writing to the database does NOT mean the transactions in that 20MB have been completed. The modifications to the database may still be rolled back if a transaction fails. You can read this case. http://social.technet.microsoft.com/Forums/is/exchangesvrgeneral/thread/86ab6c5e-d88e-4b2d-9ff5-f4b6e3a66baaTerence Yu TechNet Community Support

Hi It is very interesting topic. I remember rich explains it at the beginning of 2011. The 20MB value is the maximum amount of data that the ESE can write to logs before it writes it to the database. But transactions can span more than 20MB and on a busy server it doesn't take long to accumulate 20MB of data. So you may have many log files with uncommitted transactions, but you won't have more then four log files worth of data that hasn't been written to the database. But writing to the database does NOT mean the transactions in that 20MB have been completed. The modifications to the database may still be rolled back if a transaction fails. You can read this case. http://social.technet.microsoft.com/Forums/is/exchangesvrgeneral/thread/86ab6c5e-d88e-4b2d-9ff5-f4b6e3a66baaTerence Yu TechNet Community Support