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it is the part of code where shared resources are updates..that can be accessed by one or more then one thread of execution.It is usually terminate in a fixed time.
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What is critical region in os?
Critical region is a part of a program that must complete execution before other processes can have access to the resources being used. Processes within a critical region can't be interleaved without threatening integrity of the operation.
How is the critical region utilized in hypothesis testing?
When you formulate and test a statistical hypothesis, you compute a test statistic (a numerical value using a formula depending on the test). If the test statistic falls in the critical region, it leads us to reject our hypothesis. If it does not fall in the critical region, we do not reject our hypothesis. The critical region is a numerical interval.
What is mean by Peterson's solution in OS?
We illustrate a classic software-based solution to the critical section to the critical solution problem known as peterson's solution.
Why is security a critical issue in distributed OS environment?
I don't Know. don't ask me again..
When can a null hypothesis be rejected?
Usually when the test statistic is in the critical region.
What is critical region in operating systems?
1) CRITICAL REGIONS a) Motivation The time dependent errors can be easily generated when semaphores are used to solve the critical section problem. To overcome this difficulty a new language construct, the critical region was introduced. b) Definition and notation A variable v of type T, which is to be shared among many processes, can be declared: VAR v: SHARED T; The variable v can be accessed only inside a region statement of the following form: REGION v DO S; This construct means that while statement S is being executed, no other process can access the variable v. Thus, if the two statements, REGION v DO S1; REGION v DO S2; are executed concurrently in distinct sequential processes, the result will be equivalent to the sequential execution S1 followed by S2, or S2 followed by S1. To illustrate this construct, consider the frames CLASS defined in abstract data type. Since mutual exclusion is required when accessing the array free, we need to declare it as a shared array. VAR free: SHARED ARRAY [l..n] OF boolean; The acquire procedure must be rewritten as follows; PROCEDURE ENTRY acquire (MAR index: integer); BEGIN REGION free DO FOR index := 1 TO n DO IF free[index] THEN BEGIN free[index] := false; exit; END; index := 1; END; The critical-region construct guards against some simple errors associated with the semaphore solution to the critical section problem which may be made by a programmer. c) Compiler implementation of the critical region construct. For each declaration VAR v: SHARED T; the compiler generates a semaphore v-mutex initialized to 1. For each statement, REGION v DO S; the compiler generates the following code: p(v-mutex); S; V(v-mutex); Critical region may also be nested. In this case, however, deadlocks may result. Example of deadlock) VAR x, y: SHARED T; PARBEGIN Q: REGION x DO REGION y DO S1; R: REGION y DO REGION x DO S2; PAREND; 2) CONDITIONAL CRITICAL REGIONS The critical region construct can be effectively used to solve the critical section problem. It cannot, however, be used to solve some general synchronization problems. For this reason the conditional critical region was introduced. The major difference between the critical region and the conditional critical region constructs is in the region statement, which now has the form: REGION v WHEN B DO S; where B is a boolean expression. As before, regions referring to the same shared variable exclude each other in time. Now, however, when a process enters the critical section region. the boolean expression B is evaluated if the expression is true, statement S is executed. if it is false, the process relinquishes the mutual exclusion and is delayed until B becomes lame and no other process is in the region associated with v. Example for bounded buffer problem) VAR buffer: SHARED RECORD pool: ARRAY [0..n-l] OF item; count, in. out: integer; END; The producer process inserts a new item nextp in buffer by executing REGION buffer WHEN count < n DO BEGIN pool[in] := nextp; in := in + i MOD n; count := count + 1; END; The counter process removes an item from the shared buffer and puts it in nextc by executing: REGION buffer WHEN count > 0 DO BEGIN nextc := pool[out]; out := out +1 MOD n; count := count - 1; END; However, the CLASS concept alone cannot guarantee that such sequences will be observed. * A process might operate on the file without first gaining access permission to it; * A process might never release the file once it has been granted access to it; * A process might attempt to release a file that it never required; * A process might request the same file twice; Not that we have now encountered difficulties that are similar in nature to those that motivated us to develop the critical region construct in the first place. Previously, we had to worry about the correct use of Semaphores. Now we have to worry about the correct useo higher-level programmer-defined operations, with which the comelier can no longer assist us.
What is the meanings of non critical region in statistics?
Every possible experimental outcome results in a value of the test statistic. The non-critical region is the collection of test statistic values that are associated with acceptance of the null hypothesis.
Where is braga Portugal?
Braga is in the North, in Trás-os-Montes (the region), near Porto.
Difference between critical and non critical task in real time system?
the difference in critical and non critical task in a system is critical task are processes that the computer needs to operate correctly they are must have programs. Non critical talk are task that are running or can run but is not a crusial part if the task is deleted or ended then the OS should still fuction properly
Conditional statement inside a conditional loop?
int i = 100; while(i > 0) { // Conditional loop --i; if((i % 2) == 0) { // Conditional statement inside a conditional loop System.out.println(i + " is even."); } }
What are conditional connectives. Explain with an example?
What are conditional connectives? Explain use of conditional connectives with an example
What is the critical z value thst corresponds to a confidence level of 88 percent?
The answer will depend on whether the critical region is one-tailed or two-tailed.
