MODEL:
! Compute statistics for a multi-server queueing system (QMMC)
with Poisson arrivals, exponential service time distribution;
! Key words: queue, M/M/C queue, waiting line, staffing;
DATA:
! Get the system parameters;
R = .8333333; ! Arrival rate per minute;
T = 4; ! Mean service time in minutes;
S = 4; ! Number of servers;
DW= 5; ! Desired max wait in minutes;
ENDDATA
! The model;
! Average no. of busy servers;
LOAD = R * T;
! Fraction of calls that wait;
PWAIT = @PEB( LOAD, S);
! Conditional expected wait, i.e., given must wait;
WAITCND = T/( S - LOAD);
! Unconditional expected wait;
WAITUNC = PWAIT * WAITCND;
! Fraction calls with wait <= DW};
FWD = 1 - PWAIT*@EXP(-DW*(S/T - R));
END
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