[Xastir] rtree purge

[Tom Russo]

On Tue, Mar 01, 2005 at 06:28:26PM -0500, we recorded a bogon-computron collision of the <mckeehan at mckeehan.homeip.net> flavor, containing:
> I guess it's possible that my machine is slow enough and has such a small
> amount of RAM that the rtree stuff is getting swapped out and when I refresh
> the map, it's not rebuilding the rtree, but swapping?

I was thinking that might be a possibility, but assumed that since you 
said there was minimal memory bloat that it wouldn't have been a problem.
It seems unlikely that swap could account for the rtree fetches "taking 
forever" as you noted.  But I guess if there's a lot of thrashing it could
happen.  I'd consider that exactly the kind of excessive memory bloat I was
trying to avoid by purging unused trees.  I did at one time see the rtree
stuff bloat my xastir process to over 80M, but that doesn't happen anymore
both because I no longer use doubles in the rtree structure (thereby halving
the memory requirement), and do purge the unused rtrees.

Is this on a linux box?  If so, perhaps you could watch "top" and see if there
is a lot of swap activity at such times.  That'd pretty much settle the 
question.

-- 
Tom Russo    KM5VY     SAR502  DM64ux         http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236 AHTB#1 
 "When life gives you lemons, find someone with a paper cut."