Distributions

~name(args…)

A draw: an expression that samples a distribution each time it is evaluated. A const, a serve key and an at admission binding may not draw. The result is a number, so branch with (p) is branch (~bernoulli(p)).

Signature	Parameters	Mean	Notes
~exp(mean)	mean: expr	mean	exponential
~det(x)	x: expr	x	the constant x, as a draw
~uniform(lo, hi)	lo, hi: expr	(lo + hi) / 2	continuous on [lo, hi]
~erlang(k, mean)	k: expr, mean: expr	mean	k phases, k rounded down and at least 1
~h2(mean, cv2)	mean: expr, cv2: expr	mean	balanced two-phase hyperexponential; cv2 is the squared coefficient of variation, and values below 1 are taken as 1
~bernoulli(p)	p: expr	p	1 with probability p, else 0

Each returns a number. An argument count other than the one above is a link error.

Draws in the workload, the session and eviction keys use separate random streams, all seeded from run's seed, so a change to one does not move the others.