Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Prioritize blocked task messaging over idle tasks #627

Merged
merged 11 commits into from
Apr 18, 2024
Merged

Prioritize blocked task messaging over idle tasks #627

Changes from 1 commit
Commits
Show all changes
11 commits
Select commit Hold shift + click to select a range
3d1be8d
Prioritize blocked task messaging over idle tasks
ryoqun Apr 6, 2024
43a1bf2
Add test_scheduler_schedule_execution_blocked
ryoqun Apr 8, 2024
654a8c8
Add commentary
ryoqun Apr 8, 2024
9d1e074
Reword commentary a bit
ryoqun Apr 8, 2024
fa918be
Document not-chosen approach in detail
ryoqun Apr 13, 2024
0dca5de
Use {crossbeam,chained}_channel::unbounded()
ryoqun Apr 14, 2024
f02ebd8
Add test for race condition around SchedulingContext
ryoqun Apr 16, 2024
4e045d7
Fix race condition around SchedulingContext
ryoqun Apr 16, 2024
43ec2af
Comment about finished channels
ryoqun Apr 16, 2024
1261092
Clean up the scheduling context race test
ryoqun Apr 17, 2024
6904938
Codify hidden assumption with extra 1 recv/session
ryoqun Apr 17, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
45 changes: 33 additions & 12 deletions unified-scheduler-pool/src/lib.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -530,9 +530,13 @@ impl<S: SpawnableScheduler<TH>, TH: TaskHandler> ThreadManager<S, TH> {
}

fn start_threads(&mut self, context: &SchedulingContext) {
ryoqun marked this conversation as resolved.
Show resolved Hide resolved
let (mut runnable_task_sender, runnable_task_receiver) =
let (mut blocked_task_sender, blocked_task_receiver) =
chained_channel::unbounded::<Task, SchedulingContext>(context.clone());
let (finished_task_sender, finished_task_receiver) = unbounded::<Box<ExecutedTask>>();
let (idle_task_sender, idle_task_receiver) = unbounded::<Task>();
let (finished_blocked_task_sender, finished_blocked_task_receiver) =
unbounded::<Box<ExecutedTask>>();
let (finished_idle_task_sender, finished_idle_task_receiver) =
unbounded::<Box<ExecutedTask>>();

let mut result_with_timings = self.session_result_with_timings.take();

Expand Down Expand Up @@ -626,7 +630,7 @@ impl<S: SpawnableScheduler<TH>, TH: TaskHandler> ThreadManager<S, TH> {
// into busy looping to seek lowest latency eventually. However, not now,
// to measure _actual_ cpu usage easily with the select approach.
select! {
recv(finished_task_receiver) -> executed_task => {
recv(finished_blocked_task_receiver) -> executed_task => {
let executed_task = executed_task.unwrap();

state_machine.deschedule_task(&executed_task.task);
Expand All @@ -639,20 +643,20 @@ impl<S: SpawnableScheduler<TH>, TH: TaskHandler> ThreadManager<S, TH> {
let task = state_machine
.schedule_next_unblocked_task()
.expect("unblocked task");
runnable_task_sender.send_payload(task).unwrap();
blocked_task_sender.send_payload(task).unwrap();
},
recv(new_task_receiver) -> message => {
assert!(!session_ending);

match message.unwrap() {
NewTaskPayload::Payload(task) => {
if let Some(task) = state_machine.schedule_task(task) {
runnable_task_sender.send_payload(task).unwrap();
idle_task_sender.send(task).unwrap();
}
}
NewTaskPayload::OpenSubchannel(context) => {
// signal about new SchedulingContext to handler threads
runnable_task_sender
blocked_task_sender
.send_chained_channel(context, handler_count)
.unwrap();
assert_matches!(
Expand All @@ -665,6 +669,13 @@ impl<S: SpawnableScheduler<TH>, TH: TaskHandler> ThreadManager<S, TH> {
}
}
},
recv(finished_idle_task_receiver) -> executed_task => {
let executed_task = executed_task.unwrap();

state_machine.deschedule_task(&executed_task.task);
let result_with_timings = result_with_timings.as_mut().unwrap();
Self::accumulate_result_with_timings(result_with_timings, executed_task);
},
};

is_finished = session_ending && state_machine.has_no_active_task();
Expand All @@ -687,22 +698,32 @@ impl<S: SpawnableScheduler<TH>, TH: TaskHandler> ThreadManager<S, TH> {

let handler_main_loop = || {
let pool = self.pool.clone();
let mut runnable_task_receiver = runnable_task_receiver.clone();
let finished_task_sender = finished_task_sender.clone();
let mut blocked_task_receiver = blocked_task_receiver.clone();
let mut idle_task_receiver = idle_task_receiver.clone();
let finished_blocked_task_sender = finished_blocked_task_sender.clone();
let finished_idle_task_sender = finished_idle_task_sender.clone();

move || loop {
let (task, sender) = select! {
recv(runnable_task_receiver.for_select()) -> message => {
if let Some(task) = runnable_task_receiver.after_select(message.unwrap()) {
(task, &finished_task_sender)
recv(blocked_task_receiver.for_select()) -> message => {
if let Some(task) = blocked_task_receiver.after_select(message.unwrap()) {
(task, &finished_blocked_task_sender)
} else {
continue;
}
},
recv(idle_task_receiver) -> task => {
if let Ok(task) = task {
(task, &finished_idle_task_sender)
} else {
idle_task_receiver = never();
continue;
}
},
Copy link
Member Author

@ryoqun ryoqun Apr 6, 2024 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

here (back ref: solana-labs#34676 (comment))

};
let mut task = ExecutedTask::new_boxed(task);
Self::execute_task_with_handler(
runnable_task_receiver.context().bank(),
blocked_task_receiver.context().bank(),
&mut task,
&pool.handler_context,
);
Expand Down
Loading