Liliana Cucu
LORIA - Institut National Polytechnique de Lorraine

"Some ideas and open problems in real-time stochastic scheduling"


Validating feasibility and schedulability analyses in stochastic 
real-time scheduling  can be done either by Monte-Carlo simulations, 
either analytically. Unfortunately, simulation is not well suited to 
estimate rare events (e.g. less frequent than $10^{4}$ ) because of 
the size of the sample that is needed to achieve reasonable error bounds. 
Central Limit Theorem tell us that the convergence rate is of order 
$n^{1/2}$, where $n$ is the number of random draws, which means that 
adding one significant digit requires increasing $n$ by a factor $100$. 
Therefore we believe that an analytical validation method must be always 
preferred when one wants to validate feasibility and schedulability analyses 
in stochastic real-time scheduling.