Recent questions tagged operating-system

A FAT (file allocation table) based file system is being used and the total overhead of each entry in the FAT is $4$ bytes in size. Given a $100 \times 10^6$ bytes disk o...

Barrier is a synchronization construct where a set of processes synchronizes globally i.e., each process in the set arrives at the barrier and waits for all others to arr...

Consider the following snapshot of a system running $n$ processes. Process $i$ is holding $x_i$ instances of a resource $R$, $ 1\leq i\leq n$ . Currently, all instances ...

Consider three processes, all arriving at time zero, with total execution time of $10$, $20$ and $30$ units, respectively. Each process spends the first $20\%$ of executi...

Consider three processes (process id $0$, $1$, $2$ respectively) with compute time bursts $2$, $4$ and $8$ time units. All processes arrive at time zero. Consider the lon...

A computer system supports $32$-bit virtual addresses as well as $32$-bit physical addresses. Since the virtual address space is of the same size as the physical address ...

A CPU generates $32$-bit virtual addresses. The page size is $4$ KB. The processor has a translation look-aside buffer (TLB) which can hold a total of $128$ page table en...

The atomic fetch-and-set $x, y$ instruction unconditionally sets the memory location $x$ to $1$ and fetches the old value of $x$ in $y$ without allowing any intervening a...

Assume that there are $3$ page frames which are initially empty. If the page reference string is $\text{1, 2, 3, 4, 2, 1, 5, 3, 2, 4, 6}$ the number of page faults using ...

Consider the following set of processes that need to be scheduled on a single CPU. All the times are given in milliseconds.$$\small \begin{array}{|c|c|c|} \hline \textbf{...

An operating system uses the Banker's algorithm for deadlock avoidance when managing the allocation of three resource types $X, Y,$ and $Z$ to three processes $P0, P1,$ a...

Which one of the following is FALSE?User level threads are not scheduled by the kernel.When a user level thread is blocked, all other threads of its process are blocked.C...

Suppose a disk has $201$ cylinders, numbered from $0$ to $200$. At some time the disk arm is at cylinder $100$, and there is a queue of disk access requests for cylinders...

Fetch_And_Add(X,i) is an atomic Read-Modify-Write instruction that reads the value of memory location $X$, increments it by the value $i$, and returns the old value of $X...

Consider the $3$ processes, $P1, P2$ and $P3$ shown in the table. $$\small \begin{array}{|c|c|c|} \hline \textbf{Process} & \textbf{Arrival Time} & \textbf{Time Units Req...

Free disk space can be used to keep track of using a free list or a bit map. Disk addresses require $d$ bits. For a disk with $B$ blocks, $F$ of which are free, state the...

Four jobs are waiting to be run. Their expected run times are $6, 3, 5$ and $x.$ In what order should they be run to minimize the average response time?Write a concurrent...

If an instruction takes $i$ microseconds and a page fault takes an additional $j$ microseconds, the effective instruction time if on the average a page fault occurs every...

Consider $n$ processes sharing the CPU in a round-robin fashion. Assuming that each process switch takes $s$ seconds, what must be the quantum size $q$ such that the over...

The overlay tree for a program is as shown below:What will be the size of the partition (in physical memory) required to load (and run) this program?$\text{12 KB}$$\text{...

Formatting for a floppy disk refers toarranging the data on the disk in contiguous fashionwriting the directoryerasing the system datawriting identification information o...

A computer has six tape drives, with $n$ processes competing for them. Each process may need two drives. What is the maximum value of $n$ for the system to be deadlock fr...

A counting semaphore was initialized to $10$. Then $6 P$ (wait) operations and $4V$ (signal) operations were completed on this semaphore. The resulting value of the semap...

When the result of a computation depends on the speed of the processes involved, there is said to becycle stealingrace conditiona time locka deadlock

Which of the following is an example of a spooled device?The terminal used to enter the input data for the C program being executedAn output device used to print the outp...

Which of the following devices should get higher priority in assigning interrupts?Hard diskPrinterKeyboardFloppy disk

A certain computation generates two arrays a and b such that $a[i] = f(i)$ for $0 \leq i < n$ and $b[i] = g(a[i])$ for $0 \leq i < n$. Suppose this computation is decompo...

A shared variable $x$, initialized to zero, is operated on by four concurrent processes $W, X, Y, Z$ as follows. Each of the processes $W$ and $X$ reads $x$ from memory, ...