Crowdly

The state is unsafe, because C is left unmarked

The state is unsafe, because B is left unmarked

The state is unsafe, because A is left unmarked

For each of the following resources, indicate whether it is preemptable or non-preemptable:

Printer

Blu-Ray recorder

Memory

CPU

Select all the correct statements about Virtual File Systems

A process can use a POSIX function to read a file only if the file is stored on a partition with a UNIX file system

Each concrete partition has to implement the VFS interface

When a file is opened, a new file descriptor pointing to its i-node is created

A user process cannot directly access the concrete file systems managed by the VFS

In the UNIX V7 file system, what does a triple indirect block contain?

None of the above

Addresses of disk blocks that contain addresses of data blocks

Addresses of data blocks

Addresses of double indirect blocks

In the FAT-16 file system, how many entries can the FAT have at most?

4,096

65,536

16,000

Select the incorrect statement about files:

A file is not removed from disk when the process that created it terminates

Only one process at a time can access a file

They abstract away from file system implementation details

For each of these statements, select the file implementation it applies to:

Only part of a disk block is used to store file data

Its occupation in main memory is proportional to the number of open files

It may lead to fragmentation

Its occupation in main memory is proportional to the size of the partition

Accessing a specific byte within a file is slow

Select the incorrect statement about segmentation:

Segments can be shared among processes

The content of a segment may change during execution

All segments of a process share the same page table

Segmentation allows different memory areas to have different protection levels

Consider the FIFO, the second-chance and the clock replacement algorithms. What happens in each of these cases if the oldest page has R = 1?

FIFO

Clock

Second-chance

This question is about the working set algorithm. Suppose the current virtual time is 360ms, and τ = 50ms. The page currently being examined has:

Time of last use = 300ms

R = 1

What happens to this page?

It is evicted, as its age is bigger than τ

It is kept, and its time of last use is set to 360ms

It is kept, but is considered a candidate for eviction if no other suitable page is found