Steffen Heil (Mailinglisten) skriver: > > Hi > > > > I could simply create backups with incrementing levels, move the > > > backup to the other server(s) and apply them there (that database is > > > offline). > > > However, I suspect there is a limit for the number of backup levels a > > > database can have. > > > You don't need a lot of backup levels to do what you want. For > example, Do a level 0 backup once a month/year/whatever, then do a > > level 1 backup every weekend, a level 2 backup every day, and if > required a level 3 backup every hour/whatever. > > For another type of service I already have a backup script that > creates 5 levels of backups: > Level 0 at the first Sunday of every quarter. > Level 1 at the first Sunday every month. > Level 2 at every Sunday. > Level 3 every day. > Level 4 every hour. > > But for this project I want more than hourly consistency. I am > targeting 5 minuites or even less. That could be done using: > Level 5 every 5 minutes. > > However in this case there might be lots of days with nearly no > difference and then there may be some days with gigabytes of changes. > Using an approach as above would mean to copy all these changes up to > 23 times... > I would really like to prevent that kind of extra traffic AND more > important that delay in synchronization. > Moreover, the servers hard drives may be rather slow and the database > may grow up to 200 GB. > (During operation there are relatively few reads and only some writes, > the database is idle 99% of the time, so for operation the slow > io system is not a problem.) >
I understand your problem. Would it be possible to measure the size of each level 5 backup, and if it's over a certain threshold use a higher level for the rest of that day to keep from copying the same large set of data over and over? In essence, you would create a script that backs up every five minutes, and if the last backup size was below a certains threshold use the same level as before, otherwise bump it up. Reset to level 3 each night. The benefit is that you won't create a large number of levels unless it's actually needed to reduce backup traffic. Regards, Kjell ------------------------------------ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Visit http://www.firebirdsql.org and click the Resources item on the main (top) menu. Try Knowledgebase and FAQ links ! Also search the knowledgebases at http://www.ibphoenix.com ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Yahoo Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/firebird-support/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/firebird-support/join (Yahoo! ID required) <*> To change settings via email: [email protected] [email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo Groups is subject to: https://info.yahoo.com/legal/us/yahoo/utos/terms/
