mirrors/zed
1
0
Fork 0
mirror of https://github.com/zed-industries/zed.git synced 2025-02-03 08:54:04 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

Hold room lock through the entirety of a room_transaction

Browse source 
Previously, when the host repeatedly sent `UpdateWorktree` messages,
new guests attempting to join a project would observe a severe slowdown
caused by a database serialization error (e.g., the coherence of the data
would get violated midway through `Database::join_project` due to worktree
entries being mutated as the user joined). Writing entries is pretty fast,
whereas reading all of them for a project can take more than 100ms.
Transactions that failed due to a serialization error are retried, but the guest
would keep retrying until the host finished writing because the guest's read
was slow.

This commit changes the semantics of `room_transaction` to acquire a room
lock before even starting the transaction and holding it all the way after
commit (storing it, as before, in the `RoomGuard`). This ensures that a fast
writer (the host) can't starve a slow reader (the guest), allowing the latter
to make progress by temporarily pausing writes by the former.
This commit is contained in:
Antonio Scandurra 2023-02-22 16:04:29 +01:00
parent 24fcad3fa2
commit 8dd249a7cd
1 changed files with 112 additions and 86 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

198
crates/collab/src/db.rs
View file

@ -157,7 +157,7 @@ impl Database {
room_id: RoomId,
new_server_id: ServerId,
) -> Result<RoomGuard<RefreshedRoom>> {
self.room_transaction(|tx| async move {
self.room_transaction(room_id, |tx| async move {
let stale_participant_filter = Condition::all()
.add(room_participant::Column::RoomId.eq(room_id))
.add(room_participant::Column::AnsweringConnectionId.is_not_null())
@ -193,14 +193,11 @@ impl Database {
room::Entity::delete_by_id(room_id).exec(&*tx).await?;
}
Ok((
room_id,
RefreshedRoom {
room,
stale_participant_user_ids,
canceled_calls_to_user_ids,
},
))
Ok(RefreshedRoom {
room,
stale_participant_user_ids,
canceled_calls_to_user_ids,
})
})
.await
}
@ -1129,18 +1126,16 @@ impl Database {
user_id: UserId,
connection: ConnectionId,
live_kit_room: &str,
) -> Result<RoomGuard<proto::Room>> {
self.room_transaction(|tx| async move {
) -> Result<proto::Room> {
self.transaction(|tx| async move {
let room = room::ActiveModel {
live_kit_room: ActiveValue::set(live_kit_room.into()),
..Default::default()
}
.insert(&*tx)
.await?;
let room_id = room.id;
room_participant::ActiveModel {
room_id: ActiveValue::set(room_id),
room_id: ActiveValue::set(room.id),
user_id: ActiveValue::set(user_id),
answering_connection_id: ActiveValue::set(Some(connection.id as i32)),
answering_connection_server_id: ActiveValue::set(Some(ServerId(
@ -1157,8 +1152,8 @@ impl Database {
.insert(&*tx)
.await?;
let room = self.get_room(room_id, &tx).await?;
Ok((room_id, room))
let room = self.get_room(room.id, &tx).await?;
Ok(room)
})
.await
}
@ -1171,7 +1166,7 @@ impl Database {
called_user_id: UserId,
initial_project_id: Option<ProjectId>,
) -> Result<RoomGuard<(proto::Room, proto::IncomingCall)>> {
self.room_transaction(|tx| async move {
self.room_transaction(room_id, |tx| async move {
room_participant::ActiveModel {
room_id: ActiveValue::set(room_id),
user_id: ActiveValue::set(called_user_id),
@ -1190,7 +1185,7 @@ impl Database {
let room = self.get_room(room_id, &tx).await?;
let incoming_call = Self::build_incoming_call(&room, called_user_id)
.ok_or_else(|| anyhow!("failed to build incoming call"))?;
Ok((room_id, (room, incoming_call)))
Ok((room, incoming_call))
})
.await
}
@ -1200,7 +1195,7 @@ impl Database {
room_id: RoomId,
called_user_id: UserId,
) -> Result<RoomGuard<proto::Room>> {
self.room_transaction(|tx| async move {
self.room_transaction(room_id, |tx| async move {
room_participant::Entity::delete_many()
.filter(
room_participant::Column::RoomId
@ -1210,7 +1205,7 @@ impl Database {
.exec(&*tx)
.await?;
let room = self.get_room(room_id, &tx).await?;
Ok((room_id, room))
Ok(room)
})
.await
}
@ -1257,7 +1252,7 @@ impl Database {
calling_connection: ConnectionId,
called_user_id: UserId,
) -> Result<RoomGuard<proto::Room>> {
self.room_transaction(|tx| async move {
self.room_transaction(room_id, |tx| async move {
let participant = room_participant::Entity::find()
.filter(
Condition::all()
@ -1276,14 +1271,13 @@ impl Database {
.one(&*tx)
.await?
.ok_or_else(|| anyhow!("no call to cancel"))?;
let room_id = participant.room_id;
room_participant::Entity::delete(participant.into_active_model())
.exec(&*tx)
.await?;
let room = self.get_room(room_id, &tx).await?;
Ok((room_id, room))
Ok(room)
})
.await
}
@ -1294,7 +1288,7 @@ impl Database {
user_id: UserId,
connection: ConnectionId,
) -> Result<RoomGuard<proto::Room>> {
self.room_transaction(|tx| async move {
self.room_transaction(room_id, |tx| async move {
let result = room_participant::Entity::update_many()
.filter(
Condition::all()
@ -1316,7 +1310,7 @@ impl Database {
Err(anyhow!("room does not exist or was already joined"))?
} else {
let room = self.get_room(room_id, &tx).await?;
Ok((room_id, room))
Ok(room)
}
})
.await
@ -1328,9 +1322,9 @@ impl Database {
user_id: UserId,
connection: ConnectionId,
) -> Result<RoomGuard<RejoinedRoom>> {
self.room_transaction(|tx| async {
let room_id = RoomId::from_proto(rejoin_room.id);
self.room_transaction(room_id, |tx| async {
let tx = tx;
let room_id = RoomId::from_proto(rejoin_room.id);
let participant_update = room_participant::Entity::update_many()
.filter(
Condition::all()
@ -1549,14 +1543,11 @@ impl Database {
}
let room = self.get_room(room_id, &tx).await?;
Ok((
room_id,
RejoinedRoom {
room,
rejoined_projects,
reshared_projects,
},
))
Ok(RejoinedRoom {
room,
rejoined_projects,
reshared_projects,
})
})
.await
}
@ -1723,7 +1714,7 @@ impl Database {
connection: ConnectionId,
location: proto::ParticipantLocation,
) -> Result<RoomGuard<proto::Room>> {
self.room_transaction(|tx| async {
self.room_transaction(room_id, |tx| async {
let tx = tx;
let location_kind;
let location_project_id;
@ -1769,7 +1760,7 @@ impl Database {
if result.rows_affected == 1 {
let room = self.get_room(room_id, &tx).await?;
Ok((room_id, room))
Ok(room)
} else {
Err(anyhow!("could not update room participant location"))?
}
@ -1963,7 +1954,7 @@ impl Database {
connection: ConnectionId,
worktrees: &[proto::WorktreeMetadata],
) -> Result<RoomGuard<(ProjectId, proto::Room)>> {
self.room_transaction(|tx| async move {
self.room_transaction(room_id, |tx| async move {
let participant = room_participant::Entity::find()
.filter(
Condition::all()
@ -2024,7 +2015,7 @@ impl Database {
.await?;
let room = self.get_room(room_id, &tx).await?;
Ok((room_id, (project.id, room)))
Ok((project.id, room))
})
.await
}
@ -2034,7 +2025,8 @@ impl Database {
project_id: ProjectId,
connection: ConnectionId,
) -> Result<RoomGuard<(proto::Room, Vec<ConnectionId>)>> {
self.room_transaction(|tx| async move {
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let guest_connection_ids = self.project_guest_connection_ids(project_id, &tx).await?;
let project = project::Entity::find_by_id(project_id)
@ -2042,12 +2034,11 @@ impl Database {
.await?
.ok_or_else(|| anyhow!("project not found"))?;
if project.host_connection()? == connection {
let room_id = project.room_id;
project::Entity::delete(project.into_active_model())
.exec(&*tx)
.await?;
let room = self.get_room(room_id, &tx).await?;
Ok((room_id, (room, guest_connection_ids)))
Ok((room, guest_connection_ids))
} else {
Err(anyhow!("cannot unshare a project hosted by another user"))?
}
@ -2061,7 +2052,8 @@ impl Database {
connection: ConnectionId,
worktrees: &[proto::WorktreeMetadata],
) -> Result<RoomGuard<(proto::Room, Vec<ConnectionId>)>> {
self.room_transaction(|tx| async move {
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let project = project::Entity::find_by_id(project_id)
.filter(
Condition::all()
@ -2079,7 +2071,7 @@ impl Database {
let guest_connection_ids = self.project_guest_connection_ids(project.id, &tx).await?;
let room = self.get_room(project.room_id, &tx).await?;
Ok((project.room_id, (room, guest_connection_ids)))
Ok((room, guest_connection_ids))
})
.await
}
@ -2124,12 +2116,12 @@ impl Database {
update: &proto::UpdateWorktree,
connection: ConnectionId,
) -> Result<RoomGuard<Vec<ConnectionId>>> {
self.room_transaction(|tx| async move {
let project_id = ProjectId::from_proto(update.project_id);
let worktree_id = update.worktree_id as i64;
let project_id = ProjectId::from_proto(update.project_id);
let worktree_id = update.worktree_id as i64;
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
// Ensure the update comes from the host.
let project = project::Entity::find_by_id(project_id)
let _project = project::Entity::find_by_id(project_id)
.filter(
Condition::all()
.add(project::Column::HostConnectionId.eq(connection.id as i32))
@ -2140,7 +2132,6 @@ impl Database {
.one(&*tx)
.await?
.ok_or_else(|| anyhow!("no such project"))?;
let room_id = project.room_id;
// Update metadata.
worktree::Entity::update(worktree::ActiveModel {
@ -2220,7 +2211,7 @@ impl Database {
}
let connection_ids = self.project_guest_connection_ids(project_id, &tx).await?;
Ok((room_id, connection_ids))
Ok(connection_ids)
})
.await
}
@ -2230,9 +2221,10 @@ impl Database {
update: &proto::UpdateDiagnosticSummary,
connection: ConnectionId,
) -> Result<RoomGuard<Vec<ConnectionId>>> {
self.room_transaction(|tx| async move {
let project_id = ProjectId::from_proto(update.project_id);
let worktree_id = update.worktree_id as i64;
let project_id = ProjectId::from_proto(update.project_id);
let worktree_id = update.worktree_id as i64;
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let summary = update
.summary
.as_ref()
@ -2274,7 +2266,7 @@ impl Database {
.await?;
let connection_ids = self.project_guest_connection_ids(project_id, &tx).await?;
Ok((project.room_id, connection_ids))
Ok(connection_ids)
})
.await
}
@ -2284,8 +2276,9 @@ impl Database {
update: &proto::StartLanguageServer,
connection: ConnectionId,
) -> Result<RoomGuard<Vec<ConnectionId>>> {
self.room_transaction(|tx| async move {
let project_id = ProjectId::from_proto(update.project_id);
let project_id = ProjectId::from_proto(update.project_id);
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let server = update
.server
.as_ref()
@ -2319,7 +2312,7 @@ impl Database {
.await?;
let connection_ids = self.project_guest_connection_ids(project_id, &tx).await?;
Ok((project.room_id, connection_ids))
Ok(connection_ids)
})
.await
}
@ -2329,7 +2322,8 @@ impl Database {
project_id: ProjectId,
connection: ConnectionId,
) -> Result<RoomGuard<(Project, ReplicaId)>> {
self.room_transaction(|tx| async move {
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let participant = room_participant::Entity::find()
.filter(
Condition::all()
@ -2455,7 +2449,6 @@ impl Database {
.all(&*tx)
.await?;
let room_id = project.room_id;
let project = Project {
collaborators: collaborators
.into_iter()
@ -2475,7 +2468,7 @@ impl Database {
})
.collect(),
};
Ok((room_id, (project, replica_id as ReplicaId)))
Ok((project, replica_id as ReplicaId))
})
.await
}
@ -2485,7 +2478,8 @@ impl Database {
project_id: ProjectId,
connection: ConnectionId,
) -> Result<RoomGuard<LeftProject>> {
self.room_transaction(|tx| async move {
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let result = project_collaborator::Entity::delete_many()
.filter(
Condition::all()
@ -2521,7 +2515,7 @@ impl Database {
host_connection_id: project.host_connection()?,
connection_ids,
};
Ok((project.room_id, left_project))
Ok(left_project)
})
.await
}
@ -2531,11 +2525,8 @@ impl Database {
project_id: ProjectId,
connection_id: ConnectionId,
) -> Result<RoomGuard<Vec<ProjectCollaborator>>> {
self.room_transaction(|tx| async move {
let project = project::Entity::find_by_id(project_id)
.one(&*tx)
.await?
.ok_or_else(|| anyhow!("no such project"))?;
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let collaborators = project_collaborator::Entity::find()
.filter(project_collaborator::Column::ProjectId.eq(project_id))
.all(&*tx)
@ -2553,7 +2544,7 @@ impl Database {
.iter()
.any(|collaborator| collaborator.connection_id == connection_id)
{
Ok((project.room_id, collaborators))
Ok(collaborators)
} else {
Err(anyhow!("no such project"))?
}
@ -2566,11 +2557,8 @@ impl Database {
project_id: ProjectId,
connection_id: ConnectionId,
) -> Result<RoomGuard<HashSet<ConnectionId>>> {
self.room_transaction(|tx| async move {
let project = project::Entity::find_by_id(project_id)
.one(&*tx)
.await?
.ok_or_else(|| anyhow!("no such project"))?;
let room_id = self.room_id_for_project(project_id).await?;
self.room_transaction(room_id, |tx| async move {
let mut collaborators = project_collaborator::Entity::find()
.filter(project_collaborator::Column::ProjectId.eq(project_id))
.stream(&*tx)
@ -2583,7 +2571,7 @@ impl Database {
}
if connection_ids.contains(&connection_id) {
Ok((project.room_id, connection_ids))
Ok(connection_ids)
} else {
Err(anyhow!("no such project"))?
}
@ -2613,6 +2601,17 @@ impl Database {
Ok(guest_connection_ids)
}
async fn room_id_for_project(&self, project_id: ProjectId) -> Result<RoomId> {
self.transaction(|tx| async move {
let project = project::Entity::find_by_id(project_id)
.one(&*tx)
.await?
.ok_or_else(|| anyhow!("project {} not found", project_id))?;
Ok(project.room_id)
})
.await
}
// access tokens
pub async fn create_access_token_hash(
@ -2763,21 +2762,48 @@ impl Database {
self.run(body).await
}
async fn room_transaction<F, Fut, T>(&self, f: F) -> Result<RoomGuard<T>>
async fn room_transaction<F, Fut, T>(&self, room_id: RoomId, f: F) -> Result<RoomGuard<T>>
where
F: Send + Fn(TransactionHandle) -> Fut,
Fut: Send + Future<Output = Result<(RoomId, T)>>,
Fut: Send + Future<Output = Result<T>>,
{
let data = self
.optional_room_transaction(move |tx| {
let future = f(tx);
async {
let data = future.await?;
Ok(Some(data))
let body = async {
loop {
let lock = self.rooms.entry(room_id).or_default().clone();
let _guard = lock.lock_owned().await;
let (tx, result) = self.with_transaction(&f).await?;
match result {
Ok(data) => {
match tx.commit().await.map_err(Into::into) {
Ok(()) => {
return Ok(RoomGuard {
data,
_guard,
_not_send: PhantomData,
});
}
Err(error) => {
if is_serialization_error(&error) {
// Retry (don't break the loop)
} else {
return Err(error);
}
}
}
}
Err(error) => {
tx.rollback().await?;
if is_serialization_error(&error) {
// Retry (don't break the loop)
} else {
return Err(error);
}
}
}
})
.await?;
Ok(data.unwrap())
}
};
self.run(body).await
}
async fn with_transaction<F, Fut, T>(&self, f: &F) -> Result<(DatabaseTransaction, Result<T>)>