Delayed Jobs leaking memory?

Question

I'm using collectiveidea's delayed_job with my Ruby on Rails app (v2.3.8), and running about 40 background jobs with it on an 8GB RAM Slicehost machine (Ubuntu 10.04 LTS, Apache 2).

Let's say I ssh into my server with no workers running. When I do free -m, I'm see I'm generally using about 1GB of RAM out of 8. Then after starting the workers and waiting about a minute for them to be utilized by the code, I'm up to about 4GB. If I come back in an hour or two, I'll be at 8GB and into the swap memory, and my website will be generating 502 errors.

So far I've just been killing the workers and restarting them, but I'd rather fix the root of the problem. Any thoughts? Is this a memory leak? Or, as a friend suggested, do I need to figure out a way to run garbage collection?