Answer Posted / pranaybaldi

Readers-Writers Problem:
The readers-writers problem is a classic synchronization
problem in which two
distinct classes of threads exist, reader and writer.
Multiple reader threads
can be present in the Database simultaneously. However, the
writer threads must
have exclusive access. That is, no other writer thread, nor
any reader thread,
may be present in the Database while a given writer thread
is present. Note:
the reader/writer thread must call startRead()/startWrite()
to enter the
Database and it must call endRead()/endWrite() to exit the
Database.
class Database extends Object {
private int numReaders = 0;
private int numWriters = 0;
private ConditionVariable OKtoRead = new ConditionVariable
();
private ConditionVariable OKtoWrite = new ConditionVariable
();
public synchronized void startRead() {
while (numWriters > 0)
wait(OKtoRead);
numReaders++;
}
public synchronized void endRead() {
numReaders--;
notify(OKtoWrite);
}
public synchronized void startWrite() {
while (numReaders > 0 || numWriters > 0)
wait(OKtoWrite);
numWriters++;
}
public synchronized void endWrite() {
numWriters--;
notify(OKtoWrite);
notifyAll(OKtoRead);
}
}
class Reader extends Object implements Runnable {
private Monitor m = null;
public Reader(Monitor m) {
this.m = m;
new Thread(this).start();
}
public void run() {
//do something;
m.startRead();
//do some reading…
m.endRead();
// do something else for a long time;
}
}
class Writer extends Object implements Runnable {
private Monitor m = null;
public Writer(Monitor m) {
this.m = m;
new Thread(this).start();
}
public void run() {
//do something;
m.startWrite();
//do some writing…
m.endWrite();
// do something else for a long time;
}
}
- 2 -
wait(ConditionVariable cond) {
put the calling thread on the “wait set” of cond;
release lock;
Thread.currentThread.suspend();
acquire lock;
}
notify(ConditionVariable cond){
choose t from wait set of cond;
t.resume();
}
notifyAll(ConditionVariable cond){
forall t in wait set of cond;
t.resume()
}
For the following scenarios, we assume that only one reader
thread and one writer
thread are running on the processor.

Do you like to Submit Questions in Bulk under Same Category?? Then use our Bulk ListerDo you like to Submit Questions in Bulk under Same Category?? Then use our Bulk Lister

2082

---

What is a standard template library (stl)?

1110

---

Is stl open source?

1122

---

please visit this site you'll find my question this is my homework please answer it if you can http://easyscience.org/ib/lofiversion/index.php/t36168.html

2253

---

help me i need a c++ program which takes sequesnce of characters and outputed sequence of their token taypes, work same compiler in lexical analysis phase

2358

---

How do I convert a stl file?

1086

---

Write a C/C++ program to add a user to MySQL. The user should be permitted to only "INSERT" into the given database.

2626

---

Who wrote stl?

1116

---

How is stl different from c++ standard library?

1312

---

Explain stl.

1345

---

What is stl stand for?

1220

---

What is a standard template library (stl)? What are the various types of stl containers?

1146

---

If P is the population on the first day of the year, B is the birth rate, and D is the death rate, the estimated population at the end of the year is given by the formula: The population growth rate is given by the formula: B – D Write a program that prompts the user to enter the starting population, birth and death rates, and n, the number of years. The program should then calculate and print the estimated population after n years. Your program must have at least the following functions: 1. growthRate: This function takes its parameters the birth and death rates, and it returns the population growth rate. 2. estimatedPopulation: This function takes its parameters the current population, population growth rate, and n, the number of years. It returns the estimated population after n years Your program should not accept a negative birth rate, negative death rate, or a population less than 2. please answer my question ....

2382

---

What are stl algorithms?

1154

---

a program using one dimensional array that searches a number if it is found on the list of given input numbers given by the user and locate its exact location in the list.

1944

---