Deterministic Real-Time Allocator | Dataford Interview Questions

How would you implement a custom memory allocator for a real-time embedded system with strict deterministic execution requirements?

Implement a fixed-size arena allocator using first-fit allocation. simulate_allocator(capacity, operations) receives an integer capacity and operations ["alloc", size] or ["free", address], returning one result per operation: the allocated address, -1 on failure, or true for a successful free. Allocation must split free regions, and freeing must coalesce adjacent free regions. Assume frees reference currently allocated addresses; do not resize the arena.

Constraints: 1 <= capacity <= 1000, 1 <= len(operations) <= 1000, and allocation sizes are positive integers no greater than capacity.

Constraints

1 <= capacity <= 1000
1 <= len(operations) <= 1000
Each operation is ["alloc", size] or ["free", address]
Allocation sizes are positive integers no greater than capacity
Every free operation references a currently allocated block address
The arena never grows or moves an allocated block

Function Signature

def simulate_allocator(capacity, operations):

Your question is Deterministic Real-Time Allocator. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

How would you implement a custom memory allocator for a real-time embedded system with strict deterministic execution requirements?

Constraints: 1 <= capacity <= 1000, 1 <= len(operations) <= 1000, and allocation sizes are positive integers no greater than capacity.

Constraints

1 <= capacity <= 1000
1 <= len(operations) <= 1000
Each operation is ["alloc", size] or ["free", address]
Allocation sizes are positive integers no greater than capacity
Every free operation references a currently allocated block address
The arena never grows or moves an allocated block

Function Signature

def simulate_allocator(capacity, operations):

Your question is Deterministic Real-Time Allocator. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.