These days, my substantial programming takes place in one of twolanguages. I use Python if I'm dealing with something that doesn't haveto run fast or use minimal memory, and I use C on the occasions whenPython doesn't fit. I like C, but it is a very sparse and unforgivinglanguage when compared to Python and this translates to slower andmore annoying development most of the time; there's a lot of low leveldetails that I have to worry about when I just

I mentioned recently that we'vewritten our own system to handle ZFS spares. Before I describe it, Iwanted to write up something about why we decided to go to the extrememeasure of discarding all of ZFS's own spare handling and rolling ourown.

First off, note that our environment is unusual. We have a lot of poolsand a relatively complex SAN disk topology with at least three levels,as opposed to the more common environment of only a few pools andessentially undifferentiated disks. I expect