Low Latency Hardware-Accelerated Dynamic Memory Manager for Hard Real-Time and Mixed-Criticality Systems

Abstract

This paper presents a novel hardware architecture of dynamic memory manager providing memory allocation and deallocation operations. Due to very low and constant latency of these operations with respect to the actual number and location of free blocks of memory, the proposed solution is suitable for hard real-time and mixed-criticality systems. The proposed hardware-accelerated memory manager implements Worst-Fit algorithm for selection of a suitable free block of memory that can be used by the external environment, e.g. CPU or any custom hardware. The proposed solution uses hardware-accelerated max queue, which is a data structure that continuously provides the largest free memory block in two clock cycles regardless of the actual number or constellation of available free blocks. The proposed memory manager was verified using simplified version of UVM and applying billions of randomly generated instructions as test inputs. A synthesis into Intel FPGA Cyclone V was performed, and the synthesis results are presented as well. The memory manager was also synthesized into 28 nm technology with 1 GHz clock frequency and the power supply voltage of 0.9 V. The ASIC synthesis results show that the proposed memory manager consumes additional chip area from 35% to 70% of the managed memory.