Feature request: add torrc option to specify max physical RAM to use

It would be quite helpful for low-resource relays to be able to specify a "you shall not pass" parameter in terms of physical RAM that Tor is allowed to use. I'm not sure, if Tor runs out, how it should deal with this (refuse all new circuit creation requests until usage declines?) because I don't know the Tor internals. But this would be helpful keeping low-resource nodes more reliable, especially during DDOS conditions.

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Username: gmorehouse