Limit requests to backend based on requested domain?

[jpotter-varnish at codepuppy.com]

Hi,

Is there a way to limit the number of concurrent requests sent to a backend based on the requested domain name? Or more broadly, based on some key/value?

I know I can limit the number of requests to a backend with max requests, but our backend services multiple domains, and I’m wanting to limit the number of requests per domain (so that too many requests to one doesn’t cut off resources for others). I’ve thought of maybe doing this by defining multiple backends (pointed at the same server), but then I worry that the health checks we run would stack up (i.e. if there are a 100 domains, going from 1 backend to 100 backends would presumable increase the health checks 100 times).

Thanks,
Jeff