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* Ecole Normale Supe'rieure *
* *
* Se'minaire *
* SEMANTIQUE ET INTERPRETATION ABSTRAITE *
* P. Cousot *
* *
* Vendredi, 14h00--15h30 *
* Salle R, etage -1 *
* DI ENS 45 rue d'Ulm 75005 Paris *
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NOTER LE CHANGEMENT DE SALLE
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*** Vendredi 12 janvier 2001 **** 14h00 *****************************
Rela^che (IFIP WG 2.3)
*** Vendredi 19 janvier 2001 **** 14h00 *****************************
Rela^che (POPL'01)
*** Vendredi 26 janvier 2001 **** 14h00 *****************************
Francesco LOGOZZO (LIX)
An abstract interpretation based approach to performance modelling
Re'sume' : In last times the problem of evaluating concurrent systems
performances has been addressed by many authors. Briefly, standard
solution consists of augmenting action labels of an existing process
algebra with an exponential random variable. An exponential variable
is characterized by its parameter, so that actions in process algebra
have the form where "a" is the action performed and "r" is the
real number characterizing the random variable. Then a stochastic
process is assigned to a particular transition system and the proof of
its markiovanity is carried on.
This standard approach is unsatisfactory for two reason: - System
designer is required to specify too much information on the
architecture in early stages of designing - Just actions and
syncronizations are considered in order to assign costs to
transitions: all the other operators of process algebra are forgotten
We will show how starting from a standard pi-calculus semantics a new
stochastic algebra that avoids the above sketched problems is
designed. This semantics turns out to be more concrete than others
present in literature (as Priami's Stochastic pi-calculus).
Furthemore an abstraction from a transition system to a Markov Chain
is presented so that any proof of markovianity is required.
Eventually, as a consequence of our construction, a new bisimulation
is introduced.
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Pour recevoir l'annonce par courrier electronique: cousot@di.ens.fr
WWW: http://www.di.ens.fr/~cousot/annonceseminaire.shtml
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