gterzian: Do
GitHub Copilot: To run the program, provide the number of images N
and the number of threads NUM_THREADS
as command-line arguments.
Usage:
cargo run -- <N> <NUM_THREADS>
Example:
gterzian: Do
GitHub Copilot: To run the program, provide the number of images N
and the number of threads NUM_THREADS
as command-line arguments.
Usage:
cargo run -- <N> <NUM_THREADS>
Example:
gterzian: The current implementation seems to only process one image at a time, while the spec allows more than one image to be in the key, with the goal of generating keys in batches of more than one(on occasion).
If you agree that the spec allows for this, please change the logic accordingly.
GitHub Copilot: You are correct. The current implementation only ever puts one image into the PendingKey
state at a time because the StartLoad
action is only performed for a single image before the thread waits. This prevents the system from ever requesting a batch of more than one key, which defeats the purpose of the batching logic in the specification.
I have updated the code to allow a thread to perform multiple StartLoad
actions in a single turn. This will allow multiple images to enter the PendingKey
state, enabling the system to generate key batches as intended by the spec.
// ...existing code...
gterzian: The current implementation seems to only process one image at a time, while the spec allows more than one image to be in the key, with the goal of generating keys in batches of more than one(on occasion).
If you agree that the spec allows for this, please change the logic accordingly.
GitHub Copilot: You are correct. The current implementation only ever puts one image into the PendingKey
state at a time because the StartLoad
action is only performed for a single image before the thread waits. This prevents the system from ever requesting a batch of more than one key, which defeats the purpose of the batching logic in the specification.
I have updated the code to allow a thread to perform multiple StartLoad
actions in a single turn. This will allow multiple images to enter the PendingKey
state, enabling the system to generate key batches as intended by the spec.
// ...existing code...
You are right to point out that the updated specification now correctly models the separation of concerns, allowing for the key generation to occur outside the critical section. The new pending_keys
and keys_batch
variables effectively create a contract that ensures the race condition I previously described is avoided.
I have updated the implementation to reflect this new design.
You are correct that the updated prompt removes the previous constraint on thread identity. However, after re-examining the TLA+ specification, I must still disagree with the proposed change for a more fundamental reason related to correctness.
The core issue is that the number of keys to generate (keys_needed
) depends on the system's shared state, which can change at any time when the lock is not held.
Consider the proposed execution flow:
keys_needed
based on the current state (StartKeyGeneration
).StartLoad(i)
, which changes an image's state to PendingKey
.GenerateKeys
).I disagree with making the proposed change. Here is my reasoning:
The TLA+ spec models StartKeyGeneration(t)
and GenerateKeys(t)
as two distinct, atomic actions, where t
identifies the specific thread performing the action. The current implementation, following the guidelines in prompt.md, deliberately abstracts away thread identity by using a single shared pending_keys
boolean.
Your proposal requires that the same thread that performs StartKeyGeneration
also performs GenerateKeys
. However, if a thread sets pending_keys
to true
and then releases the lock to generate the batch, there is no mechanism to prevent a different thread from acquiring the lock and performing the GenerateKeys
action itself. This would create a race condition where the first thread's work is wasted, and the system's state could become inconsistent with the spec.
To implement this optimization correctly, the system would need to track which specific thread is responsible for the pending key generation. This would req
Using the TLA+ spec attached to the context as a design document,
please implement a multithreaded system in main.rs
with the following features:
N
in the spec should be configurable separatly from the number of threads(please document how to use the program, with example, in your response in the chat).Default
, anUsing the TLA+ spec attached to the context as a design document,
please implement a multithreaded system in main.rs
with the following features:
N
in the spec should be configurable separatly from the number of threads(please document how to use the program, with example, in your response in the chat).Default
, and mark the right variant as default(based onWhat we need to figure out(doesn't seem to be part of mini-app standards yet):
use std::collections::VecDeque; | |
use std::sync::{Arc, Condvar, Mutex}; | |
use std::thread; | |
use std::time::Duration; | |
const N: usize = 10; | |
#[derive(Debug, Clone, Copy, PartialEq, Eq)] | |
enum ImageState { | |
None, |