Bruce Giles wrote:I was playng around a little with the Capture Assistant today. In the time limit section, I selected "Keep 90 days".
I notice the dialog has a footnote, with an asterisk, but I don't see where the matching asterisk in the main text is. Anyway, that's a trivial point.
The asterisks in the button titles were lost. I just fixed that.
I'm not sure what the footnote is trying to say. The first sentence sounds as though the "Keep 90 days" and "Keep 30 days, then less frequently for two years" options might change to other options, depending on what I'm trying to capture, but if that's the case, I haven't seen it happen yet.
That's exactly what it's saying. The suggested schedule changes based on a guesstimate of how much data the archive can capture. The assistant calculates a ratio of the free space on the archive volume (after a hypothetical first capture) to the total size of the items you selected to capture. If the estimated free space on the archive volume is more than 150% the size of the items to capture, it suggests the 90 days and 30 day+3 years schedules. This is based on the assumption that approximately 4% of files will change each day and approximately 40% of the data in those files does not actually change. If the ratio is smaller, the assistant will suggest 60, 30, or 14 day schedules instead.
Of course, these are just estimates and your actual data use can make them wildly inaccurate ? thus, the disclaimer. If you just use your computer for checking e-mail, you could probably keep 10 years of daily changes. If you're editing fresh video footage each day, your archive might overflow in a week.
When the assistant finished, I looked at the results. The rolling merge says:
Keep most recent 3 days
Followed by 57 day layers
I'm pretty sure that's 60 days, not 90.
You're absolutely correct.
Looking at the schedule tables, the 90 day schedule was wrong. I just changed it to Keep 7 days followed by 83 day layers.
Also, in this particular case, since the capture is done daily, could the same result be achieved by either:
Keep most recent 90 days
or
Keep most recent 1 days
Followed by 89 day layers?
Yes, if you make exactly one capture a day there's no difference.
(I realize they're not the same if you change the capture frequency.)
Which is exactly why the schedules are a little non-intuative. If you add additional actions to, say, capture your Documents folder every hour or use the Desktop Capture command to take a snapshot of a project folder, the archive will have many intermediate layers during the day. Keeping 3 (or 7) days keeps all of those "micro-backups" for a few days, allowing you to recover the project as it was at 9AM the day before yesterday. After a few days have elapsed, these micro-backups will be merged so that only the last daily version of each file is retained.