
3-48 IBM Informix OnLine Database Server Administrator’s Guide
Plan the Archive Schedule
■ Size and number of archives. The minimum number of archives is
just the single level-0 archive. The maximum number is three, one
archive of each level.
■ Size and number of logical log files since the last archive.
The sizeof the level-0 archiveis fixed because it isthe sum of all in-usedata.
The size of the level-1 archive is a function of the time between your level-0
archives.The more oftenyou create level-0 archives,the smallereach level-1
archive will be. This same relationship holds between level-1 archives and
level-2 archives and between level-2 archives and the number of logical log
files.
Minimize Restore Time
Usethe following strategytominimize the timeneededtorestoreanOnLine
system:
■ Createalevel-0archiveasoftenasispracticable,perhapseverythree
days.
■ Create a level-1 archive daily.
■ Do not use level-2 archives.
The time required for any possible restore is limited to the time needed to
read and process the following data:
■ A level-0 archive, representing the whole system
■ A level-1 archive, representing from one to three days’ activity
■ Logical log files, representing less than a day’s work
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