One of our production systems has a slice called "oldslice" that periodically runs low on space during normal operation. We have minimum requirements for online data retention, and whoever sized this slice didn't give it much wiggle room, so it periodically runs low on space. I'm getting tired of archive files every other week in response to low space alerts.

I discovered(I inherited these systems ) that there is an unused slice on the same drive that is several times larger than then problematic one.

I've used newfs to make a filesystem on the unused slice, and have mounted it under /mnt/newslice .

Now I want to duplicate oldslice's contents to newslice. There are a number of ways to do this, but I want the most reliable and least resource intensive one to do it while the system is active.

This looks promising if it doesn't use too many resources -

Code:

 
cd dir1 && tar -cf – . | (cd dir2 && tar -xpvf -)

ideas?