Updates to indicate if an automatic recompute of aggregate d

[skyewright]

Sometimes I find that installing an update leads to an automatic recomputation of data. Sometimes not.

Installing 2.7c (from 2.7b) seems to have caused one.

So far as I'm aware the only way for me to tell is to do the install, then wait for around 10 minutes to see if a re-computation starts.

This is relevant because recomputation puts a heavy load on my NSLU2 for around 4.5 hours with current data size and I like to stop the feed to WSWIN and WD while it is going on to give the NSLU2 the best chance.

If I knew whether or not a recomputation was likley I could better choose the timing of installs for minimal disruption.

From the fearures mentioned I hadn't expected 2.7b => 2.7c to cause a recompute. If I had I'd have left the update till a more convenient time...