When varnish cache is empty and I got X client requests for the same asset - Varnish gathers the clients and issues 1 backend fetch.
Do you know if there's possibility to control how many requests are held until fetch (or time window size)? - I would like to have backend fetch more frequently so the clients would wait shorter time.
When I test with return(pass) - I got nice flow, no long times for the client, but I got no caching - and because caching is set by backend - I would like to stay with "return(lookup)" which enables antidogpile effect - good but sometimes bad (because of holding reqs...)
EDIT: Kind of solution in my comments :)