fix(buffer): Optimistically initialize stacks as ready

relay-server/src/services/buffer/envelope_buffer/mod.rs

@@ -292,7 +292,7 @@ where
  },
  Priority {
  readiness,
- next_project_fetch: next_peek,
+ next_project_fetch,
  ..
  },
  )) = self.priority_queue.peek_mut()
@@ -305,7 +305,7 @@ where
  Ok(match (stack.peek().await?, ready) {
  (None, _) => Peek::Empty,
  (Some(envelope), true) => Peek::Ready(envelope),
- (Some(envelope), false) => Peek::NotReady(*stack_key, *next_peek, envelope),
+ (Some(envelope), false) => Peek::NotReady(*stack_key, *next_project_fetch, envelope),
  })
  }
 
@@ -607,9 +607,11 @@ struct Readiness {
 
 impl Readiness {
  fn new() -> Self {
+ // Optimistically set ready state to true.
+ // The large majority of stack creations are re-creations after a stack was emptied.
  Self {
- own_project_ready: false,
- sampling_project_ready: false,
+ own_project_ready: true,
+ sampling_project_ready: true,
  }
  }
 

relay-server/src/services/buffer/mod.rs

@@ -237,7 +237,7 @@ impl EnvelopeBufferService {
  self.services.project_cache.send(DequeuedEnvelope(envelope));
  self.sleep = Duration::ZERO; // try next pop immediately
  }
- Peek::NotReady(stack_key, next_peek, envelope) => {
+ Peek::NotReady(stack_key, next_project_fetch, envelope) => {
  relay_log::trace!("EnvelopeBufferService: project(s) of envelope not ready");
  relay_statsd::metric!(
  counter(RelayCounters::BufferTryPop) += 1,
@@ -247,7 +247,7 @@ impl EnvelopeBufferService {
  // We want to fetch the configs again, only if some time passed between the last
  // peek of this not ready project key pair and the current peek. This is done to
  // avoid flooding the project cache with `UpdateProject` messages.
- if Instant::now() >= next_peek {
+ if Instant::now() >= next_project_fetch {
  relay_log::trace!("EnvelopeBufferService: requesting project(s) update");
  let project_key = envelope.meta().public_key();
  self.services.project_cache.send(UpdateProject(project_key));