[Haskell-cafe] Re: Tree traversal / stack overflow

[Matthew Eastman]

Turns out I was building the trees wrong, ended up getting a structure  
that looked like a linked list (each tree only had 1 child) so the  
depth of the recursion was way higher than it should've been. Crisis  
averted!

Still seemed odd that the garbage collector ran for so much of the  
time, so I checked and there's a ticket in GHC trac about it: http://hackage.haskell.org/trac/ghc/ticket/2236 
.

On 20-May-09, at 12:02 AM, Matthew Eastman wrote:

> ...
>
> The code I have right now works great on point sets of size ~10,000,  
> but when I go up much higher things start to go wrong. I start  
> hitting stack overflows, so I increased the stack size. For ~100,000  
> points though, running the code with +RTS -sstderr -K128m it chugged  
> along for over an hour and then died with a stack overflow. The  
> stats said it spent 50 seconds MUT time and 5300 seconds (almost 90  
> minutes!) GC time, which seems odd.
>
> ...