Re: Database backup causes hanging...

Nicholas Wee (scornd11@solomon.technet.sg) wrote: : Hello, : We have an Informix Online 5.0 running on a HP 9000. : Problem: When a level 0 archive is being performed, : database access is not possible. : It seems that when the process is backing up a harddisk : containing BLOBs (200MB) and during this time a checkpoint : is invoked, : DATA ACCESS WILL HANG !!! : : When the backup for that harddisk (containing BLOBs) is over AND the : data backup is now BACKING UP harddisks containing NORMAL data, AND : during this time a CHECKPOINT is invoked : DATA ACCESS WILL NOT HANG !!! : Question: Can we raise the checkpoint interval so that checkpoints NEVER : occur during the BACKING UP of a harddisk containing BLOBs. : Answer: Yes, we can. Raise the checkpoint interval to 45 minutes. : This is the time it takes to backup BLOB data. : Question: Are there any drawbacks to this ? : Answer: Informix GARRENTEES that FAST RECOVERY (after system crash) : is 2 MINUTES for a 5 MINUTE checkpoint interval. A 45 MINUTE : checkpoint interval might mean that FAST RECOVERY takes more than 5 : MINUTES : This is UNACCEPTABLE. : Question: Is there another solution ? : Answer: Build a process that makes Informix checkpoint every 5 MINUTES. : Before the process calls for a checkpoint, it makes sure that : the data backup process is not running. This process runs : continuously, day after day... : Question: This means that during a data backup, if system crashes, : Informix will take more than 5 MINUTES to recover ??? : Answer: Yes... : Does anyone have any other solutions ? : Thanks in advance. : Ivy. Inteligencia can provide a method of backup without disruption. As well as many features not available with tbtape. ******************************************************************************** __ _ _ __ () , _ / ) // ' ) ) /`-'| // / _/_ / / __. // _ /--' / / o // /___/> __ / /__/_(_/|_</_</_ / \\ o /__-<_<_</_/_) (__/ (_<__ Dale R. Gilbert DGC/4GL email: dgc@netcom.com 1256 Cabrillo Ave., Suite 250 FAX: (310) 320-3579 Torrance, CA 90501 VOICE: (310) 320-4300 ******************************************************************************** Inteligencia: The ONLY Row Level Backup/Restore Solution for Informix OnLine(r) ******************************************************************************** -- ******************************************************************************** __ _ _ __ () , _ / ) // ' ) ) /`-'| // / _/_ / / __. // _ /--' / / o // /___/> __ / /__/_(_/|_</_</_ / \\ o /__-<_<_</_/_) (__/ (_<__ Dale R. Gilbert DGC/4GL email: dgc@netcom.com 1256 Cabrillo Ave., Suite 250 FAX: (310) 320-3579 Torrance, CA 90501 VOICE: (310) 320-4300 ******************************************************************************** Inteligencia: The ONLY Row Level Backup/Restore Solution for Informix OnLine(r) ********************************************************************************