C
ChUIMonster
Guest
I always use -com. The amount of savings varies from "not much" to "quite a bit". It is not "zip" style compression though. As I understand it it just skips empty space. So if your data extents are very densely packed it probably won't do much for you except to save a few IO ops. After backing up with -com I then often gzip the backup and that usually gets to roughly 1/5th the size of the original db. I'd be thrilled if real zip style compression were built-in to probkup/prorest. CPU cycles and RAM are plentiful. IO ops are precious. Zipping the data would burn CPU cycles and RAM but save quite a few IO ops. I'd like to be able to easily make that trade off. I know that we could, in theory, backup to a pipe and run it through gzip but that's really kind of klunky for my taste. A built-in option would be much easier to work with. Tip: you should also use -Bp 10 with online probkup -- that prevents the backup from polluting the buffer pool as it reads the db.
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