This is a simulator of a dynamic random-access memory (DRAM) for the simplescalar simulator.

The simulator has a file with specs definition. The file must follow the next structure:

dram:
    capacity: 1
    clock: 4
    chips:
        number: 2
        banks: 16
        rows: 1000
        columns: 32000
        capacity: 512
    times:
        RP: 1
        RCD: 1
        CL: 1
    wait:
        latency: 0
        bus_free: 0

You can find this example in specs.yml.

To execute the simulator with a diferent specs file use $ python dram.py <path>

A lot.

• The capacity of the DRAM must be expressed in GB
• The clock of the DRAM must expressed in processor clock cycles
• The chips[capacity] must be expressed in MB
• All of the times must be expressed in DRAM clock cycles
• The DRAM[capacity] must be equal to chips[capacity] * chips[number]. This is the chips capacity per number of chips equals the total capacity of the DRAM.
• The chips[capacity] in Bytes must be equal to the number of chips[rows] * chips[banks] * chips[columns] expressed in Bytes.
• All given valuen must be positive and all DRAM[chips] values must be pair

To use this DRAM simulator as a simulator for the simplescalar we must run the dram.py script in one process and another process should be the simplescalar itself. The simplescalar simulator will do its task (execute tests or benchmarks) and will write into a file called 'memory_content.txt' the next structure:

block_size mode address now_time

The dram script will process that data and return to simplescalar a 'signal' file with the total time of transfer time, latency time and wait of the simulated DRAM according to the given information by 'memory_content.txt'. simplescalar will acknowledge the 'signal' file and continue writing into 'memory_content.txt' more data. After every file reading both programs delete the file they were reading from, simplescalar deletes signal and creates a memory_content.txt file every time and the dram script delete memory_content.txt and creates a signal file every time.