perf: bounded concurrent Qdrant setup I/O via buffer_unordered

[Copilot]

The previous try_join_all refactor achieved concurrency but with unbounded fan-out — N collections meant N simultaneous Qdrant requests, risking connection storms and server overload. Review feedback requested bounded concurrency, race-condition safety documentation, and reduced duplication.

Changes

• Bounded concurrency: replaced try_join_all with buffer_unordered(MAX_CONCURRENT_SETUP_OPS) (cap: 16). Futures are pre-collected via a for loop + Vec::with_capacity before being streamed — required to satisfy async_trait's HRTB lifetime constraints, which prevent using iter().map() directly with buffer_unordered.

• Race-condition invariant documented: added a comment confirming CollectionKey uniqueness is enforced by the setup orchestration layer, so intra-phase concurrent ops cannot race on the same collection.

• Constant for the concurrency limit: MAX_CONCURRENT_SETUP_OPS = 16 makes the bound discoverable and easy to tune.

let mut delete_futures = Vec::with_capacity(setup_change.len());
for change in setup_change.iter() {
    let client_result = self.get_qdrant_client(&change.key.connection, auth_registry);
    delete_futures.push(async move {
        change.setup_change.apply_delete(&change.key.collection_name, &client_result?).await
    });
}
futures::stream::iter(delete_futures)
    .buffer_unordered(MAX_CONCURRENT_SETUP_OPS)
    .try_collect::<Vec<_>>().await.map(|_| ())?;

Phase ordering (all deletes before any creates) is preserved.

---

🔒 GitHub Advanced Security automatically protects Copilot coding agent pull requests. You can protect all pull requests by enabling Advanced Security for your repositories. Learn more about Advanced Security.

[cloudflare-workers-and-pages]

Deploying with    Cloudflare Workers

The latest updates on your project. Learn more about integrating Git with Workers.

Status	Name	Latest Commit	Preview URL	Updated (UTC)
✅ Deployment successful! View logs	recoco-docs	538324f	Commit Preview URL Branch Preview URL	Mar 13 2026, 03:39 AM

[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• test
  • Triggering command: /home/REDACTED/work/recoco/recoco/target/debug/deps/recoco_core-cf2701bcf874797c /home/REDACTED/work/recoco/recoco/target/debug/deps/recoco_core-cf2701bcf874797c lib --emit=dep-info,metadata -C opt-level=1 -C embed-bitcode=no .18/src/lib.rs codegen-units=256 -C debuginfo=2 -C s/th�� fccbfb73.dptdgc2--error-format=json s/thiserror_impl--json=diagnostic-rendered-ansi,artifacts,future-incompat bin/rustc lib/rustlib/x86_/home/REDACTED/.rustup/toolchains/stable-x86_64-REDACTED-linux-gnu/bin/clippy-drive-m64 lib/rustlib/x86_/home/REDACTED/.rustup/toolchains/stable-x86_64-REDACTED-linux-gnu/bin/rustc lib/rustlib/x86_--crate-name bin/rustc (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

[Copilot]

Pull request overview

This PR bounds concurrent Qdrant collection setup I/O to prevent unbounded request fan-out during delete/create phases while preserving phase ordering.

Changes:

• Introduces MAX_CONCURRENT_SETUP_OPS and runs setup ops via buffer_unordered to cap concurrency.
• Adds an invariant comment about CollectionKey uniqueness to justify safe intra-phase concurrency.
• Reworks delete/create phases to pre-collect futures and then execute them with bounded concurrency.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.