Question

200 memory units and 100 disk units are available to the operating system. process a is using 50 memory units and can claim 100. process b is using 10 memory units and can claim 30 units. process c is using 20 memory units and can claim 60. process d is using 40 memory units and can claim 80. process a is using 25 disk units and can claim 50. process b is using 10 disk units and can claim 15 units. process c is using 20 disk units and can claim 40. process d is using 20 disk units and can claim 50. process a requests an additional 45 memory units and 10 disk units. can the os grant the request? show you work

Answer 1

The operating system should not grant process A's request for additional resources, as doing so may lead to a situation where the sum of maximum resource claims exceeds the total resources available, presenting a risk of deadlock.

Step-by-step explanation:

The student's question pertains to the possibility of an operating system granting a request for additional memory and disk units to a process within the constraints of the system's available resources. The scenario involves resource allocation and is part of the operating system subject area. To determine if the operating system can grant the request from process A, we need to consider the current usage and maximum claims of resources (both memory and disk) by all processes and the total resources available.

Memory Allocation:

Total memory available: 200 units

Memory used by processes: 50 + 10 + 20 + 40 = 120 units

Total memory that can be claimed: 100 + 30 + 60 + 80 = 270 units

Additional memory request by process A: 45 units

Total available memory after granting request: 200 - 120 - 45 = 35 units

Total claims after granting request: 270 - 50 + 45 = 265 units

Since the total memory that can be claimed (265 units) exceeds the remaining available memory (35 units), it is risky to grant the request without further checks for a safe state.

Disk Allocation:

Total disk units available: 100 units

Disk used by processes: 25 + 10 + 20 + 20 = 75 units

Total disk that can be claimed: 50 + 15 + 40 + 50 = 155 units

Additional disk request by process A: 10 units

Total available disk after granting request: 100 - 75 - 10 = 15 units

Total claims after granting request: 155 - 25 + 10 = 140 units

Since the total disk that can be claimed (140 units) is close to the remaining available disk (15 units), this is also a risky situation and could lead to a deadlock.

Based on the above calculations, it is not advisable for the operating system to grant the request from process A for an additional 45 memory units and 10 disk units as it could potentially lead to a situation where the sum of the maximum resource claims exceeds the total resources available, risking a deadlock situation.