TradeStation 2000i Source Code of Select Programs in .NET

Encoding QR-Code in .NET TradeStation 2000i Source Code of Select Programs

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10.5. Conclusion Markovian aggregation methods reduce the size of the Markov chain to be solved to obtain the performance indices of discrete event systems. Stochastic well-formed Petri nets take advantage of Markovian aggregation for systems modeled with stochastic Petri nets and with behavioral symmetries. Taking these symmetries into account in the de nition of colored nets, we have developed ef cient resolution methods, that is without computing the non-aggregated Markov chain. With the help of the symbolic reachability graph built from the description of the well-formed net, we are able to de ne and analyze an aggregated Markov chain of the Markov chain of the colored stochastic Petri net. Moreover, the states of each aggregate, a set of colored markings, are equiprobable. The reduction ratio of the size of the studied Markov chain is obviously related to the symmetry level in the system, and may be very high as shown by many examples. In the next chapter, we present the tensorial approach, the goal of which is also to reduce the resolution complexity of the Markov chain, and we show how to combine these two methods.

How fast is code being constructed Does the implemented code correspond to the highest priority features/ requirements scheduled for the current iteration

For example, a memory barrier instruction can be located within the instance() method of the Singleton template adapter class: template <class TYPE> TYPE *Singleton<TYPE>::instance () { TYPE *tmp = instance_; #if defined (ALPHA_MP) // Insert the CPU-specific memory barrier instruction // to synchronize the cache lines on multi-processor. asm ("mb"); #endif /* ALPHA_MP */ // First check if (tmp == 0) { // Scoped Locking acquires and releases lock. Guard<Thread_Mutex> guard (singleton_lock_); // Double check. if (tmp == 0) { tmp = new TYPE; #if defined (ALPHA_MP) // Insert a second CPU-specific memory // barrier instruction. asm ("mb"); #endif /* ALPHA_MP */