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can the process of rusting be called combustion discuss process facilitation

Another interesting issue is the underlying protocol used in client-server communication. Figure 2-15 shows six packet types that are commonly used to implement client-server protocols. The first one is the REQ packet, used to send a request message from a client to a server. (For simplicity, for the rest of this section we will assume that each message fits in a single packet.) The next one is the REP packet that carries results back from the server to the client. Then comes the ACK packet, which is used in reliable protocols to confirm the correct receipt of a previous packet.. Fig. 2-18. Calls and messages in an RPC. Each ellipse represents a single process, with the shaded portion being the stub.. Solution 3 is a variant on this idea, but less Draconian. It is calledgentle reincarnation. When an epoch broadcast comes in, each machine checks to see if it has any remote computations, and if so, tries to locate their owner. Only if the owner cannot be found is the computation killed.. Fig. 2-28. (a) Timeouts in a sorted list. (b) Timeouts in the process table.. The presence of gateways can affect many properties of the implementation. To start with, multicasting becomes more complicated. Consider, for example, the internetwork shown in Fig. 2-36. It consists of four LANs and four gateways, to provide protection against the failure of any gateway.. Fig. 3-22. Concurrency control using timestamps.. 4.1.3. Design Issues for Threads Packages. every (25 msec) {… }. As a final thought, it should be pointed out that our discussion has simplified matters considerably. For example, tasks may need access to shared variables, so these have to be reserved in advance. Often there are scheduling constraints, which we have ignored. Finally, some systems do advance planning during runtime, making them hybrids between static and dynamic.. In short, weak consistency, release consistency, and entry consistency require additional programming constructs that, when used as directed, allow programmers to pretend that memory is sequentially consistent, when, in fact, it is not. In principle, these three models using explicit synchronization should be able to offer the best performance, but it is likely that different applications will give quite different results. More research is needed before we can draw any firm conclusions here.. For these reasons, page-based DSM systems typically use an invalidation protocol instead of an update protocol. Various protocols are possible. Below we will describe a typical example, in which all pages are potentially writable (i.e., the DSM software does not know what is on which page).. The extra information required by Midway should be thought of as part of the contract between the software and the memory that we studied earlier under consistency. In effect, if the program agrees to abide by certain rules known in advance, the memory promises to work. Otherwise, all bets are off. Implementation. 6. During the discussion of memory consistency models, we often referred to the contract between the software and memory. Why is such a contract needed?. 9.2.2. Threads. 10.7. DISTRIBUTED FILE SYSTEM.