limiting disk usage

>From what I read in the Polipo Manual it seems that I can't set the maximum disk space occupied by Polipo cache. Do I read that correct? What's the best way to achieve it?

Let's say I don't have much control how much data will flow through the proxy. It might be a lot. But I don't have unlimited disk space. I would like to limit Polipo disk usage to 10GB. I definitely don't want Polipo to deplete all available disk space and take down the whole server and all services running there. Of course I can run cron job and trim files periodically, but that doesn't help me when there is a high spike in network activity and dozens of GBs are downloaded in an hour. I can't run the cron job every minute. I would be very satisfied if Polipo could limit its disk usage and replace the oldest files with the new files if the that threshold is reached.

I can create a separate disk partition just for Polipo cache, yes. But that has several drawbacks. Is there a better way?

Moreover, what will happen if Polipo runs out of available disk space?

Thanks,
Kamil

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