RMagick

I have stumbled upon an odd bug, and it is confirmed on both my local [Windows] dev box and my remote shared host.

I have a tileset, for all intents and purposes it contains:
upper left, upper * n, upper right
west, middle * n, east
lower left, lower * n, lower right

This allows me to create grid (n+2)*(n+2)

I append them together as row1, row2, and row3
Then I make an ImageList of row1, 20 row2's, and row3
I go to do a vertical append (append(true) in Ruby) - and my CPU jumps to full load.

I let the task run for about 45 minutes before I decided that shit wasn't finishing.

If I put row1, 2, and 3 to disk, and append those vertically - it works just fine.

If I do this with far smaller numbers (row1 being 3 units wide, instead of 23) - it seems to work OK.

I'm stumped, /prog/ - does anyone have experience with ImageMagick that could explain this shit?

[Windows] dev box
near complete lack of context
description of what you think it should do rather than actual code
These are but three of your problems.