From 6036830049422ce765535cc4b16374f71b8eaf33 Mon Sep 17 00:00:00 2001 From: Max Brunsfeld Date: Wed, 6 Mar 2024 05:58:41 -0800 Subject: [PATCH] Throttle the sending of UpdateFollowers messages (#8918) ## Problem We're trying to figure out why we sometimes see high latency when collaborating, even though the collab server logs indicate that messages are not taking long to process. We think that high volumes of certain types of messages, including `UpdateFollowers` may cause a lot of messages to queue up, causing delays before collab sees certain messages. ## Fix This PR reduces the number of `UpdateFollowers` messages that clients send to collab when scrolling around or moving the cursor, using a time-based throttle. The downside of this change is that scrolling will not be as smooth when following someone. The advantage is that it will be much easier to keep up with the stream of updates, since they will be sent much less frequently. ## Release Notes: - Fixed slowness that could occur when collaborating due to excessive messages being sent to support following. --------- Co-authored-by: Nathan Co-authored-by: Conrad Co-authored-by: Antonio Scandurra Co-authored-by: Thorsten Co-authored-by: Thorsten Ball --- Cargo.lock | 1 + crates/collab/src/tests/following_tests.rs | 9 ++ crates/gpui/src/test.rs | 2 +- crates/picker/Cargo.toml | 1 + crates/picker/src/picker.rs | 41 +++++++-- crates/workspace/src/item.rs | 98 ++++++++++++++-------- crates/workspace/src/workspace.rs | 2 +- 7 files changed, 109 insertions(+), 45 deletions(-) diff --git a/Cargo.lock b/Cargo.lock index c012316eaa6c8c2eb0f5049f0a2365ab7e600f84..483b56d9995608dd0d686a3361186eaa0f1f63d9 100644 --- a/Cargo.lock +++ b/Cargo.lock @@ -6960,6 +6960,7 @@ dependencies = [ name = "picker" version = "0.1.0" dependencies = [ + "anyhow", "ctor", "editor", "env_logger", diff --git a/crates/collab/src/tests/following_tests.rs b/crates/collab/src/tests/following_tests.rs index 57e53880452eb74898051fe283d4e06af50aec04..0dff43e41b24895b18be7bb1e2a669e1938daa4e 100644 --- a/crates/collab/src/tests/following_tests.rs +++ b/crates/collab/src/tests/following_tests.rs @@ -373,8 +373,10 @@ async fn test_basic_following( editor_a1.update(cx_a, |editor, cx| { editor.change_selections(None, cx, |s| s.select_ranges([1..1, 2..2])); }); + executor.advance_clock(workspace::item::LEADER_UPDATE_THROTTLE); executor.run_until_parked(); cx_b.background_executor.run_until_parked(); + editor_b1.update(cx_b, |editor, cx| { assert_eq!(editor.selections.ranges(cx), &[1..1, 2..2]); }); @@ -387,6 +389,7 @@ async fn test_basic_following( editor.change_selections(None, cx, |s| s.select_ranges([3..3])); editor.set_scroll_position(point(0., 100.), cx); }); + executor.advance_clock(workspace::item::LEADER_UPDATE_THROTTLE); executor.run_until_parked(); editor_b1.update(cx_b, |editor, cx| { assert_eq!(editor.selections.ranges(cx), &[3..3]); @@ -1598,6 +1601,8 @@ async fn test_following_stops_on_unshare(cx_a: &mut TestAppContext, cx_b: &mut T editor_a.update(cx_a, |editor, cx| { editor.change_selections(None, cx, |s| s.select_ranges([1..1])) }); + cx_a.executor() + .advance_clock(workspace::item::LEADER_UPDATE_THROTTLE); cx_a.run_until_parked(); editor_b.update(cx_b, |editor, cx| { assert_eq!(editor.selections.ranges(cx), vec![1..1]) @@ -1616,6 +1621,8 @@ async fn test_following_stops_on_unshare(cx_a: &mut TestAppContext, cx_b: &mut T editor_a.update(cx_a, |editor, cx| { editor.change_selections(None, cx, |s| s.select_ranges([2..2])) }); + cx_a.executor() + .advance_clock(workspace::item::LEADER_UPDATE_THROTTLE); cx_a.run_until_parked(); editor_b.update(cx_b, |editor, cx| { assert_eq!(editor.selections.ranges(cx), vec![1..1]) @@ -1720,6 +1727,7 @@ async fn test_following_into_excluded_file( // When client B starts following client A, currently visible file is replicated workspace_b.update(cx_b, |workspace, cx| workspace.follow(peer_id_a, cx)); + executor.advance_clock(workspace::item::LEADER_UPDATE_THROTTLE); executor.run_until_parked(); let editor_for_excluded_b = workspace_b.update(cx_b, |workspace, cx| { @@ -1741,6 +1749,7 @@ async fn test_following_into_excluded_file( editor_for_excluded_a.update(cx_a, |editor, cx| { editor.select_right(&Default::default(), cx); }); + executor.advance_clock(workspace::item::LEADER_UPDATE_THROTTLE); executor.run_until_parked(); // Changes from B to the excluded file are replicated in A's editor diff --git a/crates/gpui/src/test.rs b/crates/gpui/src/test.rs index eab11e7b4c0a646bd1743e306ee80f89b78a0260..3f267542f8178f23091eecb3e845ec748fac9ab0 100644 --- a/crates/gpui/src/test.rs +++ b/crates/gpui/src/test.rs @@ -46,10 +46,10 @@ pub fn run_test( let starting_seed = env::var("SEED") .map(|seed| seed.parse().expect("invalid SEED variable")) .unwrap_or(0); - let is_randomized = num_iterations > 1; if let Ok(iterations) = env::var("ITERATIONS") { num_iterations = iterations.parse().expect("invalid ITERATIONS variable"); } + let is_randomized = num_iterations > 1; for seed in starting_seed..starting_seed + num_iterations { let mut retry = 0; diff --git a/crates/picker/Cargo.toml b/crates/picker/Cargo.toml index 79a8ed70d832fe112efd8bdf50fa14854193f670..435e4459e93e962ea6fe9de57f1ec026fc79c668 100644 --- a/crates/picker/Cargo.toml +++ b/crates/picker/Cargo.toml @@ -13,6 +13,7 @@ path = "src/picker.rs" doctest = false [dependencies] +anyhow.workspace = true editor.workspace = true gpui.workspace = true menu.workspace = true diff --git a/crates/picker/src/picker.rs b/crates/picker/src/picker.rs index 11c2458ee1d53d53234052a7c94f9743ea024f0f..6ff9f62e0f0bfd947373b039c79d3fb20b014c33 100644 --- a/crates/picker/src/picker.rs +++ b/crates/picker/src/picker.rs @@ -1,3 +1,4 @@ +use anyhow::Result; use editor::Editor; use gpui::{ div, list, prelude::*, uniform_list, AnyElement, AppContext, ClickEvent, DismissEvent, @@ -15,11 +16,16 @@ enum ElementContainer { UniformList(UniformListScrollHandle), } +struct PendingUpdateMatches { + delegate_update_matches: Option>, + _task: Task>, +} + pub struct Picker { pub delegate: D, element_container: ElementContainer, editor: View, - pending_update_matches: Option>, + pending_update_matches: Option, confirm_on_update: Option, width: Option, max_height: Option, @@ -281,15 +287,32 @@ impl Picker { } pub fn update_matches(&mut self, query: String, cx: &mut ViewContext) { - let update = self.delegate.update_matches(query, cx); + let delegate_pending_update_matches = self.delegate.update_matches(query, cx); + self.matches_updated(cx); - self.pending_update_matches = Some(cx.spawn(|this, mut cx| async move { - update.await; - this.update(&mut cx, |this, cx| { - this.matches_updated(cx); - }) - .ok(); - })); + // This struct ensures that we can synchronously drop the task returned by the + // delegate's `update_matches` method and the task that the picker is spawning. + // If we simply capture the delegate's task into the picker's task, when the picker's + // task gets synchronously dropped, the delegate's task would keep running until + // the picker's task has a chance of being scheduled, because dropping a task happens + // asynchronously. + self.pending_update_matches = Some(PendingUpdateMatches { + delegate_update_matches: Some(delegate_pending_update_matches), + _task: cx.spawn(|this, mut cx| async move { + let delegate_pending_update_matches = this.update(&mut cx, |this, _| { + this.pending_update_matches + .as_mut() + .unwrap() + .delegate_update_matches + .take() + .unwrap() + })?; + delegate_pending_update_matches.await; + this.update(&mut cx, |this, cx| { + this.matches_updated(cx); + }) + }), + }); } fn matches_updated(&mut self, cx: &mut ViewContext) { diff --git a/crates/workspace/src/item.rs b/crates/workspace/src/item.rs index 25d9f5ed8946efcd964d4c62f6d30bd62c5baff7..07ca2c06a7bcf7aa5af7dbf768d3ccaf8dc7fa03 100644 --- a/crates/workspace/src/item.rs +++ b/crates/workspace/src/item.rs @@ -11,6 +11,7 @@ use client::{ proto::{self, PeerId}, Client, }; +use futures::{channel::mpsc, StreamExt}; use gpui::{ AnyElement, AnyView, AppContext, Entity, EntityId, EventEmitter, FocusHandle, FocusableView, HighlightStyle, Model, Pixels, Point, SharedString, Task, View, ViewContext, WeakView, @@ -27,14 +28,13 @@ use std::{ ops::Range, path::PathBuf, rc::Rc, - sync::{ - atomic::{AtomicBool, Ordering}, - Arc, - }, + sync::Arc, time::Duration, }; use theme::Theme; +pub const LEADER_UPDATE_THROTTLE: Duration = Duration::from_millis(200); + #[derive(Deserialize)] pub struct ItemSettings { pub git_status: bool, @@ -415,7 +415,7 @@ impl ItemHandle for View { followed_item.is_project_item(cx), proto::update_followers::Variant::CreateView(proto::View { id: followed_item - .remote_id(&workspace.app_state.client, cx) + .remote_id(&workspace.client(), cx) .map(|id| id.to_proto()), variant: Some(message), leader_id: workspace.leader_for_pane(&pane), @@ -431,8 +431,46 @@ impl ItemHandle for View { .is_none() { let mut pending_autosave = DelayedDebouncedEditAction::new(); + let (pending_update_tx, mut pending_update_rx) = mpsc::unbounded(); let pending_update = Rc::new(RefCell::new(None)); - let pending_update_scheduled = Arc::new(AtomicBool::new(false)); + + let mut send_follower_updates = None; + if let Some(item) = self.to_followable_item_handle(cx) { + let is_project_item = item.is_project_item(cx); + let item = item.downgrade(); + + send_follower_updates = Some(cx.spawn({ + let pending_update = pending_update.clone(); + |workspace, mut cx| async move { + while let Some(mut leader_id) = pending_update_rx.next().await { + while let Ok(Some(id)) = pending_update_rx.try_next() { + leader_id = id; + } + + workspace.update(&mut cx, |workspace, cx| { + let item = item.upgrade().expect( + "item to be alive, otherwise task would have been dropped", + ); + workspace.update_followers( + is_project_item, + proto::update_followers::Variant::UpdateView( + proto::UpdateView { + id: item + .remote_id(workspace.client(), cx) + .map(|id| id.to_proto()), + variant: pending_update.borrow_mut().take(), + leader_id, + }, + ), + cx, + ); + })?; + cx.background_executor().timer(LEADER_UPDATE_THROTTLE).await; + } + anyhow::Ok(()) + } + })); + } let mut event_subscription = Some(cx.subscribe(self, move |workspace, item, event, cx| { @@ -448,9 +486,7 @@ impl ItemHandle for View { }; if let Some(item) = item.to_followable_item_handle(cx) { - let is_project_item = item.is_project_item(cx); let leader_id = workspace.leader_for_pane(&pane); - let follow_event = item.to_follow_event(event); if leader_id.is_some() && matches!(follow_event, Some(FollowEvent::Unfollow)) @@ -458,35 +494,13 @@ impl ItemHandle for View { workspace.unfollow(&pane, cx); } - if item.focus_handle(cx).contains_focused(cx) - && item.add_event_to_update_proto( + if item.focus_handle(cx).contains_focused(cx) { + item.add_event_to_update_proto( event, &mut pending_update.borrow_mut(), cx, - ) - && !pending_update_scheduled.load(Ordering::SeqCst) - { - pending_update_scheduled.store(true, Ordering::SeqCst); - cx.defer({ - let pending_update = pending_update.clone(); - let pending_update_scheduled = pending_update_scheduled.clone(); - move |this, cx| { - pending_update_scheduled.store(false, Ordering::SeqCst); - this.update_followers( - is_project_item, - proto::update_followers::Variant::UpdateView( - proto::UpdateView { - id: item - .remote_id(&this.app_state.client, cx) - .map(|id| id.to_proto()), - variant: pending_update.borrow_mut().take(), - leader_id, - }, - ), - cx, - ); - } - }); + ); + pending_update_tx.unbounded_send(leader_id).ok(); } } @@ -535,6 +549,7 @@ impl ItemHandle for View { cx.observe_release(self, move |workspace, _, _| { workspace.panes_by_item.remove(&item_id); event_subscription.take(); + send_follower_updates.take(); }) .detach(); } @@ -715,6 +730,7 @@ pub trait FollowableItem: Item { pub trait FollowableItemHandle: ItemHandle { fn remote_id(&self, client: &Arc, cx: &WindowContext) -> Option; + fn downgrade(&self) -> Box; fn set_leader_peer_id(&self, leader_peer_id: Option, cx: &mut WindowContext); fn to_state_proto(&self, cx: &WindowContext) -> Option; fn add_event_to_update_proto( @@ -743,6 +759,10 @@ impl FollowableItemHandle for View { }) } + fn downgrade(&self) -> Box { + Box::new(self.downgrade()) + } + fn set_leader_peer_id(&self, leader_peer_id: Option, cx: &mut WindowContext) { self.update(cx, |this, cx| this.set_leader_peer_id(leader_peer_id, cx)) } @@ -782,6 +802,16 @@ impl FollowableItemHandle for View { } } +pub trait WeakFollowableItemHandle: Send + Sync { + fn upgrade(&self) -> Option>; +} + +impl WeakFollowableItemHandle for WeakView { + fn upgrade(&self) -> Option> { + Some(Box::new(self.upgrade()?)) + } +} + #[cfg(any(test, feature = "test-support"))] pub mod test { use super::{Item, ItemEvent}; diff --git a/crates/workspace/src/workspace.rs b/crates/workspace/src/workspace.rs index b4cb71c45a7f2cde3b4fb886160185977bf52855..50631ba7360d983622cbf67a1aa01ab219f83f16 100644 --- a/crates/workspace/src/workspace.rs +++ b/crates/workspace/src/workspace.rs @@ -1108,7 +1108,7 @@ impl Workspace { ) } - pub fn client(&self) -> &Client { + pub fn client(&self) -> &Arc { &self.app_state.client }