Avoid temporary allocations by improved APIs

mdbook/src/chapter_2/chapter_2_4.md

@@ -80,7 +80,7 @@ fn main() {
 
             // Acquire a re-activator for this operator.
             use timely::scheduling::Scheduler;
-            let activator = scope.activator_for(&info.address[..]);
+            let activator = scope.activator_for(info.address);
 
             let mut cap = Some(capability);
             move |output| {

timely/src/dataflow/channels/pact.rs

@@ -26,7 +26,7 @@ pub trait ParallelizationContract<T, C> {
     /// Type implementing `Pull` produced by this pact.
     type Puller: Pull<Bundle<T, C>>+'static;
     /// Allocates a matched pair of push and pull endpoints implementing the pact.
-    fn connect<A: AsWorker>(self, allocator: &mut A, identifier: usize, address: &[usize], logging: Option<Logger>) -> (Self::Pusher, Self::Puller);
+    fn connect<A: AsWorker>(self, allocator: &mut A, identifier: usize, address: Vec<usize>, logging: Option<Logger>) -> (Self::Pusher, Self::Puller);
 }
 
 /// A direct connection
@@ -36,7 +36,7 @@ pub struct Pipeline;
 impl<T: 'static, C: Container> ParallelizationContract<T, C> for Pipeline {
     type Pusher = LogPusher<T, C, ThreadPusher<Bundle<T, C>>>;
     type Puller = LogPuller<T, C, ThreadPuller<Bundle<T, C>>>;
-    fn connect<A: AsWorker>(self, allocator: &mut A, identifier: usize, address: &[usize], logging: Option<Logger>) -> (Self::Pusher, Self::Puller) {
+    fn connect<A: AsWorker>(self, allocator: &mut A, identifier: usize, address: Vec<usize>, logging: Option<Logger>) -> (Self::Pusher, Self::Puller) {
         let (pusher, puller) = allocator.pipeline::<Message<T, C>>(identifier, address);
         (LogPusher::new(pusher, allocator.index(), allocator.index(), identifier, logging.clone()),
          LogPuller::new(puller, allocator.index(), identifier, logging))
@@ -72,7 +72,7 @@ where
     type Pusher = ExchangePusher<T, C, LogPusher<T, C, Box<dyn Push<Bundle<T, C>>>>, H>;
     type Puller = LogPuller<T, C, Box<dyn Pull<Bundle<T, C>>>>;
 
-    fn connect<A: AsWorker>(self, allocator: &mut A, identifier: usize, address: &[usize], logging: Option<Logger>) -> (Self::Pusher, Self::Puller) {
+    fn connect<A: AsWorker>(self, allocator: &mut A, identifier: usize, address: Vec<usize>, logging: Option<Logger>) -> (Self::Pusher, Self::Puller) {
         let (senders, receiver) = allocator.allocate::<Message<T, C>>(identifier, address);
         let senders = senders.into_iter().enumerate().map(|(i,x)| LogPusher::new(x, allocator.index(), i, identifier, logging.clone())).collect::<Vec<_>>();
         (ExchangePusher::new(senders, self.hash_func), LogPuller::new(receiver, allocator.index(), identifier, logging.clone()))

timely/src/dataflow/operators/capability.rs

@@ -347,10 +347,10 @@ impl<T: Timestamp> CapabilityTrait<T> for ActivateCapability<T> {
 
 impl<T: Timestamp> ActivateCapability<T> {
     /// Creates a new activating capability.
-    pub fn new(capability: Capability<T>, address: &[usize], activations: Rc<RefCell<Activations>>) -> Self {
+    pub fn new(capability: Capability<T>, address: Vec<usize>, activations: Rc<RefCell<Activations>>) -> Self {
         Self {
             capability,
-            address: Rc::new(address.to_vec()),
+            address: Rc::new(address),
             activations,
         }
     }

timely/src/dataflow/operators/core/capture/replay.rs

@@ -72,7 +72,7 @@ where
         let mut builder = OperatorBuilder::new("Replay".to_owned(), scope.clone());
 
         let address = builder.operator_info().address;
-        let activator = scope.activator_for(&address[..]);
+        let activator = scope.activator_for(address);
 
         let (targets, stream) = builder.new_output();
 

timely/src/dataflow/operators/core/enterleave.rs

@@ -62,7 +62,7 @@ impl<G: Scope, T: Timestamp+Refines<G::Timestamp>, C: Data+Container> Enter<G, T
         let ingress = IngressNub {
             targets: Counter::new(targets),
             phantom: PhantomData,
-            activator: scope.activator_for(&scope.addr()),
+            activator: scope.activator_for(scope.addr()),
             active: false,
         };
         let produced = ingress.targets.produced().clone();

timely/src/dataflow/operators/core/input.rs

@@ -153,10 +153,9 @@ impl<G: Scope> Input for G where <G as ScopeParent>::Timestamp: TotalOrder {
         let produced = counter.produced().clone();
 
         let index = self.allocate_operator_index();
-        let mut address = self.addr();
-        address.push(index);
+        let address = self.addr_for_child(index);
 
-        handle.activate.push(self.activator_for(&address[..]));
+        handle.activate.push(self.activator_for(address.clone()));
 
         let progress = Rc::new(RefCell::new(ChangeBatch::new()));
 

timely/src/dataflow/operators/core/to_stream.rs

@@ -37,7 +37,7 @@ impl<CB: ContainerBuilder, I: IntoIterator+'static> ToStreamBuilder<CB> for I wh
         source::<_, CB, _, _>(scope, "ToStreamBuilder", |capability, info| {
 
             // Acquire an activator, so that the operator can rescheduled itself.
-            let activator = scope.activator_for(&info.address[..]);
+            let activator = scope.activator_for(info.address);
 
             let mut iterator = self.into_iter().fuse();
             let mut capability = Some(capability);

timely/src/dataflow/operators/core/unordered_input.rs

@@ -91,10 +91,9 @@ impl<G: Scope> UnorderedInput<G> for G {
         let peers = self.peers();
 
         let index = self.allocate_operator_index();
-        let mut address = self.addr();
-        address.push(index);
+        let address = self.addr_for_child(index);
 
-        let cap = ActivateCapability::new(cap, &address, self.activations());
+        let cap = ActivateCapability::new(cap, address.clone(), self.activations());
 
         let helper = UnorderedHandle::new(counter);
 

timely/src/dataflow/operators/flow_controlled.rs

@@ -87,7 +87,7 @@ pub fn iterator_source<
     let mut target = G::Timestamp::minimum();
     source(scope, name, |cap, info| {
         let mut cap = Some(cap);
-        let activator = scope.activator_for(&info.address[..]);
+        let activator = scope.activator_for(info.address);
         move |output| {
             cap = cap.take().and_then(|mut cap| {
                 loop {

timely/src/dataflow/operators/generic/builder_raw.rs

@@ -70,8 +70,7 @@ impl<G: Scope> OperatorBuilder<G> {
 
         let global = scope.new_identifier();
         let index = scope.allocate_operator_index();
-        let mut address = scope.addr();
-        address.push(index);
+        let address = scope.addr_for_child(index);
         let peers = scope.peers();
 
         OperatorBuilder {
@@ -119,7 +118,7 @@ impl<G: Scope> OperatorBuilder<G> {
 
         let channel_id = self.scope.new_identifier();
         let logging = self.scope.logging();
-        let (sender, receiver) = pact.connect(&mut self.scope, channel_id, &self.address[..], logging);
+        let (sender, receiver) = pact.connect(&mut self.scope, channel_id, self.address.clone(), logging);
         let target = Target::new(self.index, self.shape.inputs);
         stream.connect_to(target, sender, channel_id);
 
@@ -175,7 +174,7 @@ impl<G: Scope> OperatorBuilder<G> {
 
     /// Information describing the operator.
     pub fn operator_info(&self) -> OperatorInfo {
-        OperatorInfo::new(self.index, self.global, &self.address[..])
+        OperatorInfo::new(self.index, self.global, self.address.clone())
     }
 }
 

timely/src/dataflow/operators/generic/builder_rc.rs

@@ -64,7 +64,7 @@ impl<G: Scope> OperatorBuilder<G> {
     where
         P: ParallelizationContract<G::Timestamp, C> {
 
-        let connection = vec![Antichain::from_elem(Default::default()); self.builder.shape().outputs()];
+        let connection = (0..self.builder.shape().outputs()).map(|_| Antichain::from_elem(Default::default())).collect();
         self.new_input_connection(stream, pact, connection)
     }
 
@@ -94,7 +94,7 @@ impl<G: Scope> OperatorBuilder<G> {
 
     /// Adds a new output to a generic operator builder, returning the `Push` implementor to use.
     pub fn new_output<CB: ContainerBuilder>(&mut self) -> (OutputWrapper<G::Timestamp, CB, Tee<G::Timestamp, CB::Container>>, StreamCore<G, CB::Container>) {
-        let connection = vec![Antichain::from_elem(Default::default()); self.builder.shape().inputs()];
+        let connection = (0..self.builder.shape().inputs()).map(|_| Antichain::from_elem(Default::default())).collect();
         self.new_output_connection(connection)
     }
 

timely/src/dataflow/operators/generic/operator.rs

@@ -535,7 +535,7 @@ impl<G: Scope, C1: Container> Operator<G, C1> for StreamCore<G, C1> {
 ///
 ///     source(scope, "Source", |capability, info| {
 ///
-///         let activator = scope.activator_for(&info.address[..]);
+///         let activator = scope.activator_for(info.address);
 ///
 ///         let mut cap = Some(capability);
 ///         move |output| {

timely/src/dataflow/operators/generic/operator_info.rs

@@ -12,11 +12,11 @@ pub struct OperatorInfo {
 
 impl OperatorInfo {
     /// Construct a new `OperatorInfo`.
-    pub fn new(local_id: usize, global_id: usize, address: &[usize]) -> OperatorInfo {
+    pub fn new(local_id: usize, global_id: usize, address: Vec<usize>) -> OperatorInfo {
         OperatorInfo {
             local_id,
             global_id,
-            address: address.to_vec(),
+            address,
         }
     }
 }

timely/src/dataflow/scopes/child.rs

@@ -58,10 +58,10 @@ where
     fn config(&self) -> &Config { self.parent.config() }
     fn index(&self) -> usize { self.parent.index() }
     fn peers(&self) -> usize { self.parent.peers() }
-    fn allocate<D: Data>(&mut self, identifier: usize, address: &[usize]) -> (Vec<Box<dyn Push<Message<D>>>>, Box<dyn Pull<Message<D>>>) {
+    fn allocate<D: Data>(&mut self, identifier: usize, address: Vec<usize>) -> (Vec<Box<dyn Push<Message<D>>>>, Box<dyn Pull<Message<D>>>) {
         self.parent.allocate(identifier, address)
     }
-    fn pipeline<D: 'static>(&mut self, identifier: usize, address: &[usize]) -> (ThreadPusher<Message<D>>, ThreadPuller<Message<D>>) {
+    fn pipeline<D: 'static>(&mut self, identifier: usize, address: Vec<usize>) -> (ThreadPusher<Message<D>>, ThreadPuller<Message<D>>) {
         self.parent.pipeline(identifier, address)
     }
     fn new_identifier(&mut self) -> usize {
@@ -97,6 +97,15 @@ where
 {
     fn name(&self) -> String { self.subgraph.borrow().name.clone() }
     fn addr(&self) -> Vec<usize> { self.subgraph.borrow().path.clone() }
+
+    fn addr_for_child(&self, index: usize) -> Vec<usize> {
+        let path = &self.subgraph.borrow().path[..];
+        let mut addr = Vec::with_capacity(path.len() + 1);
+        addr.extend_from_slice(path);
+        addr.push(index);
+        addr
+    }
+
     fn add_edge(&self, source: Source, target: Target) {
         self.subgraph.borrow_mut().connect(source, target);
     }

timely/src/dataflow/scopes/mod.rs

@@ -33,6 +33,10 @@ pub trait Scope: ScopeParent {
     /// A sequence of scope identifiers describing the path from the worker root to this scope.
     fn addr(&self) -> Vec<usize>;
 
+    /// A sequence of scope identifiers describing the path from the worker root to the child
+    /// indicated by `index`.
+    fn addr_for_child(&self, index: usize) -> Vec<usize>;
+
     /// Connects a source of data with a target of the data. This only links the two for
     /// the purposes of tracking progress, rather than effect any data movement itself.
     fn add_edge(&self, source: Source, target: Target);

timely/src/progress/broadcast.rs

@@ -31,16 +31,15 @@ pub struct Progcaster<T:Timestamp> {
 
 impl<T:Timestamp+Send> Progcaster<T> {
     /// Creates a new `Progcaster` using a channel from the supplied worker.
-    pub fn new<A: crate::worker::AsWorker>(worker: &mut A, path: &Vec<usize>, mut logging: Option<Logger>, progress_logging: Option<ProgressLogger>) -> Progcaster<T> {
+    pub fn new<A: crate::worker::AsWorker>(worker: &mut A, addr: Vec<usize>, mut logging: Option<Logger>, progress_logging: Option<ProgressLogger>) -> Progcaster<T> {
 
         let channel_identifier = worker.new_identifier();
-        let (pushers, puller) = worker.allocate(channel_identifier, &path[..]);
+        let (pushers, puller) = worker.allocate(channel_identifier, addr.clone());
         logging.as_mut().map(|l| l.log(crate::logging::CommChannelsEvent {
             identifier: channel_identifier,
             kind: crate::logging::CommChannelKind::Progress,
         }));
         let worker_index = worker.index();
-        let addr = path.clone();
         Progcaster {
             to_push: None,
             pushers,

timely/src/progress/subgraph.rs

@@ -131,14 +131,16 @@ where
 
     /// Adds a new child to the subgraph.
     pub fn add_child(&mut self, child: Box<dyn Operate<TInner>>, index: usize, identifier: usize) {
-        {
-            let mut child_path = self.path.clone();
+        if let Some(l) = &mut self.logging {
+            let mut child_path = Vec::with_capacity(self.path.len() + 1);
+            child_path.extend_from_slice(&self.path[..]);
             child_path.push(index);
-            self.logging.as_mut().map(|l| l.log(crate::logging::OperatesEvent {
+
+            l.log(crate::logging::OperatesEvent {
                 id: identifier,
                 addr: child_path,
                 name: child.name().to_owned(),
-            }));
+            });
         }
         self.children.push(PerOperatorState::new(child, index, self.path.clone(), identifier, self.logging.clone()))
     }
@@ -163,7 +165,8 @@ where
         let mut builder = reachability::Builder::new();
 
         // Child 0 has `inputs` outputs and `outputs` inputs, not yet connected.
-        builder.add_node(0, outputs, inputs, vec![vec![Antichain::new(); inputs]; outputs]);
+        let summary = (0..outputs).map(|_| (0..inputs).map(|_| Antichain::new()).collect()).collect();
+        builder.add_node(0, outputs, inputs, summary);
         for (index, child) in self.children.iter().enumerate().skip(1) {
             builder.add_node(index, child.inputs, child.outputs, child.internal_summary.clone());
         }
@@ -181,7 +184,7 @@ where
             .map(|logger| reachability::logging::TrackerLogger::new(path, logger));
         let (tracker, scope_summary) = builder.build(reachability_logging);
 
-        let progcaster = Progcaster::new(worker, &self.path, self.logging.clone(), self.progress_logging.clone());
+        let progcaster = Progcaster::new(worker, self.path.clone(), self.logging.clone(), self.progress_logging.clone());
 
         let mut incomplete = vec![true; self.children.len()];
         incomplete[0] = false;

timely/src/scheduling/activate.rs

@@ -224,9 +224,9 @@ pub struct Activator {
 
 impl Activator {
     /// Creates a new activation handle
-    pub fn new(path: &[usize], queue: Rc<RefCell<Activations>>) -> Self {
+    pub fn new(path: Vec<usize>, queue: Rc<RefCell<Activations>>) -> Self {
         Self {
-            path: path.to_vec(),
+            path,
             queue,
         }
     }
@@ -259,9 +259,9 @@ pub struct SyncActivator {
 
 impl SyncActivator {
     /// Creates a new thread-safe activation handle.
-    pub fn new(path: &[usize], queue: SyncActivations) -> Self {
+    pub fn new(path: Vec<usize>, queue: SyncActivations) -> Self {
         Self {
-            path: path.to_vec(),
+            path,
             queue,
         }
     }

timely/src/scheduling/mod.rs

@@ -26,12 +26,12 @@ pub trait Scheduler {
     fn activations(&self) -> Rc<RefCell<Activations>>;
 
     /// Constructs an `Activator` tied to the specified operator address.
-    fn activator_for(&self, path: &[usize]) -> Activator {
+    fn activator_for(&self, path: Vec<usize>) -> Activator {
         Activator::new(path, self.activations())
     }
 
     /// Constructs a `SyncActivator` tied to the specified operator address.
-    fn sync_activator_for(&self, path: &[usize]) -> SyncActivator {
+    fn sync_activator_for(&self, path: Vec<usize>) -> SyncActivator {
         let sync_activations = self.activations().borrow().sync();
         SyncActivator::new(path, sync_activations)
     }

timely/src/synchronization/sequence.rs

@@ -128,7 +128,7 @@ impl<T: ExchangeData> Sequencer<T> {
                 activator_source
                     .borrow_mut()
                     .replace(CatchupActivator {
-                        activator: scope.activator_for(&info.address[..]),
+                        activator: scope.activator_for(info.address),
                         catchup_until: None,
                     });
 

timely/src/worker.rs

@@ -191,12 +191,12 @@ pub trait AsWorker : Scheduler {
     /// scheduled in response to the receipt of records on the channel.
     /// Most commonly, this would be the address of the *target* of the
     /// channel.
-    fn allocate<T: Data>(&mut self, identifier: usize, address: &[usize]) -> (Vec<Box<dyn Push<Message<T>>>>, Box<dyn Pull<Message<T>>>);
+    fn allocate<T: Data>(&mut self, identifier: usize, address: Vec<usize>) -> (Vec<Box<dyn Push<Message<T>>>>, Box<dyn Pull<Message<T>>>);
     /// Constructs a pipeline channel from the worker to itself.
     ///
     /// By default this method uses the native channel allocation mechanism, but the expectation is
     /// that this behavior will be overriden to be more efficient.
-    fn pipeline<T: 'static>(&mut self, identifier: usize, address: &[usize]) -> (ThreadPusher<Message<T>>, ThreadPuller<Message<T>>);
+    fn pipeline<T: 'static>(&mut self, identifier: usize, address: Vec<usize>) -> (ThreadPusher<Message<T>>, ThreadPuller<Message<T>>);
 
     /// Allocates a new worker-unique identifier.
     fn new_identifier(&mut self) -> usize;
@@ -231,17 +231,17 @@ impl<A: Allocate> AsWorker for Worker<A> {
     fn config(&self) -> &Config { &self.config }
     fn index(&self) -> usize { self.allocator.borrow().index() }
     fn peers(&self) -> usize { self.allocator.borrow().peers() }
-    fn allocate<D: Data>(&mut self, identifier: usize, address: &[usize]) -> (Vec<Box<dyn Push<Message<D>>>>, Box<dyn Pull<Message<D>>>) {
+    fn allocate<D: Data>(&mut self, identifier: usize, address: Vec<usize>) -> (Vec<Box<dyn Push<Message<D>>>>, Box<dyn Pull<Message<D>>>) {
         if address.is_empty() { panic!("Unacceptable address: Length zero"); }
         let mut paths = self.paths.borrow_mut();
-        paths.insert(identifier, address.to_vec());
+        paths.insert(identifier, address);
         self.temp_channel_ids.borrow_mut().push(identifier);
         self.allocator.borrow_mut().allocate(identifier)
     }
-    fn pipeline<T: 'static>(&mut self, identifier: usize, address: &[usize]) -> (ThreadPusher<Message<T>>, ThreadPuller<Message<T>>) {
+    fn pipeline<T: 'static>(&mut self, identifier: usize, address: Vec<usize>) -> (ThreadPusher<Message<T>>, ThreadPuller<Message<T>>) {
         if address.is_empty() { panic!("Unacceptable address: Length zero"); }
         let mut paths = self.paths.borrow_mut();
-        paths.insert(identifier, address.to_vec());
+        paths.insert(identifier, address);
         self.temp_channel_ids.borrow_mut().push(identifier);
         self.allocator.borrow_mut().pipeline(identifier)
     }