This Happy Eyeballs (RFC 8305) tuning directive specifies the
	minimum delay between opening spare to-server connections (to any
	server; i.e. across all concurrent master transactions in a Squid
	instance). Each SMP worker currently multiplies the configured gap
	by the total number of workers so that the combined spare connection
	opening rate of a Squid instance obeys the configured limit. The
	workers do not coordinate connection openings yet; a micro burst
	of spare connection openings may violate the configured gap.

	This directive has similar trade-offs as
	happy_eyeballs_connect_timeout, but its focus is on limiting traffic
	amplification effects for Squid as a whole, while
	happy_eyeballs_connect_timeout works on an individual master
	transaction level.

	The following Happy Eyeballs directives place additional connection
	opening restrictions: happy_eyeballs_connect_timeout and
	happy_eyeballs_connect_limit. See the former for related terminology.