Hi all, I would need to suspend the FS simulation after a certain number of ticks, and then have it resume normally. I know that for SE mode this is feasible by inserting `m5.simulate()` in a loop and passing as an argument to the same function the number of ticks it should simulate. Is there an analogue for FS mode? I am using `/gem5/configs/example/riscv/fs_linux.py`

Or, at least, I would need to do it in such a way as to have the historical progression of the "stats.txt" file during the simulation. So I need to suspend the simulation at a certain tick, get the "stats.txt" file, resume the simulation, or I need a solution that allows me to dump at a certain tick.

checkpoint_interval = 1e7  # Example: every 10 million ticks
next_checkpoint = checkpoint_interval

while m5.curTick() < num_ticks:
    m5.simulate(min(checkpoint_interval, num_ticks - m5.curTick()))
    print("Current tick:", m5.curTick())
    m5.stats.dump()  # dump the stats

    if m5.curTick() >= next_checkpoint:
        m5.checkpoint('checkpoint%d' % (m5.curTick()))
        next_checkpoint += checkpoint_interval

Hello, Unfortunately, we don't have enough time to answer all questions in depth. You may be able to find more help on either the gem5 slack <https://www.gem5.org/join-slack> or the gem5 youtube channel <https://www.youtube.com/@gem5>. If you have access to ChatGPT Plus, you can also use the gem5 GPT <https://chat.openai.com/g/g-o3y1y4t8J-gem5-gpt>. In fact, we have found that most of the LLMs do a good job answering gem5-related questions. In the meantime, here is the output from the gem5 GPT for your question. This answer has not been checked for correctness, but our experience is that the answers from the gem5 GPT at a minimum point in the right direction. Suspending and resuming a Full System (FS) simulation in gem5, similar to what you've described for System-call Emulation (SE) mode, is indeed possible. In FS mode, you can control the simulation flow using the Python configuration scripts, just as you do in SE mode. However, there are some nuances to consider when dealing with FS simulations. For your specific use case, where you want to suspend the simulation after a certain number of ticks, retrieve the `stats.txt` file, and then resume, you can follow these steps: 1. **Modify the Python Script**: - Open the `/gem5/configs/example/riscv/fs_linux.py` script. - In this script, you can insert a loop that calls `m5.simulate()` for a specified number of ticks. After each `m5.simulate()` call, the script will regain control, allowing you to perform operations like dumping statistics. - Here's an example of how you might modify the script: ```python import m5 from m5.objects import * # existing configuration code... num_ticks = 1e9 # Example: 1 billion ticks while m5.curTick() < num_ticks: m5.simulate(1000000) # simulate for 1 million ticks at a time print("Current tick:", m5.curTick()) m5.stats.dump() # dump the stats ``` - This script will now run the simulation in chunks of 1 million ticks, dumping the statistics after each chunk. 2. **Dumping Statistics**: - The `m5.stats.dump()` call will update the `stats.txt` file. Make sure you have set up your statistics correctly in the simulation configuration so that they are captured and written to the file. 3. **Resuming the Simulation**: - The loop will automatically continue the simulation until it reaches the specified number of ticks. There's no need for explicit "resume" commands, as `m5.simulate()` both starts and resumes the simulation. 4. **Periodic Checkpoints (Optional)**: - If you want to be able to resume the simulation from a particular point, not just dump statistics, consider using checkpoints. You can create a checkpoint at each loop iteration or at specific intervals. Here's how you can add checkpoint creation: ```python checkpoint_interval = 1e7 # Example: every 10 million ticks next_checkpoint = checkpoint_interval while m5.curTick() < num_ticks: m5.simulate(min(checkpoint_interval, num_ticks - m5.curTick())) print("Current tick:", m5.curTick()) m5.stats.dump() # dump the stats if m5.curTick() >= next_checkpoint: m5.checkpoint('checkpoint%d' % (m5.curTick())) next_checkpoint += checkpoint_interval ``` - This will create a checkpoint file every 10 million ticks (or at the specified interval). 5. **Considerations for FS Mode**: - In FS mode, especially with complex simulations, be aware that there might be additional complications, such as device states and interactions with the simulated OS. Always test your modified script to ensure that it behaves as expected. 6. **Running the Modified Script**: - Once you've modified your `fs_linux.py` script, run it as you normally would to start the simulation. By following these steps, you should be able to achieve your goal of suspending the FS simulation at specific tick intervals, dumping the stats, and then resuming the simulation. Remember that gem5 is a complex tool, and small changes in the simulation script can have significant impacts on the behavior and performance of your simulation, so careful testing and validation of your modified script are recommended. On Tue, Jan 16, 2024 at 1:16 AM elio.vinciguerra--- via gem5-users < gem5-users@gem5.org> wrote: > Or, at least, I would need to do it in such a way as to have the > historical progression of the "stats.txt" file during the simulation. So I > need to suspend the simulation at a certain tick, get the "stats.txt" file, > resume the simulation, or I need a solution that allows me to dump at a > certain tick. > _______________________________________________ > gem5-users mailing list -- gem5-users@gem5.org > To unsubscribe send an email to gem5-users-leave@gem5.org >