Copy monthly/yearly archives from daily #35
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A daily archive is created automatically. If monthly and/or yearly archives are missing, they are copied from the daily archive: `tarsnap -c -f monthly @@daily` This also ensures that there is always a daily, monthly, and yearly backup. The copy operation should be low-resource and very fast. It requires only reading the entry metadata from the daily archive.
| # No yearly backup | ||
| log_debug "message=\"Copying daily archive to yearly archive\"" | ||
| archive_starttime=$(date +%s) | ||
| log_verbose "copy-start type=yearly dir=/$dir name=$yearlyarchive" |
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if the copy process is relatively quick, are the copy-start messages needed? There will always be either a copy-error or copy-finish message
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I threw them in for consistency with the archive operation, but I am always a fan of simpler output. I’ll happily take them out.
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The copy time scales with the number of files in the archive, not the size of the archive. For archives with a huge number of files, the copy time will be less than the backup time, but still noticeable.
assistcontrol
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Jun 15, 2019
Previously, the first day of the year would create a yearly archive, the second day would create a monthly, and the third would create a daily archive. With this change, yearly, monthly, and daily archives always exist. Daily archives are created every time acts is run. If monthly and/or yearly archives don't exist, the new daily archive is copied to the other(s). Copies are based on metadata. That metadata must be read and parsed, which causes some data transfer. However, that data is quite minimal and should impose very little cost. Copies do take some time to run. The time scales with the number of files in the archive, not with the size of each file. And though time scales, it scales very slowly. In my tests, copies are faster than archive creation for all but the smallest archives of 1-5 files. Copies are substantially faster for large archives.
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A daily archive is created automatically. If monthly and/or yearly
archives are missing, they are copied from the daily archive:
tarsnap -c -f monthly @@dailyThis also ensures that there is always a daily, monthly, and yearly
backup.
The copy operation should be low-resource and very fast. It
requires only reading the entry metadata from the daily archive.