nodedb 0.2.0

Local-first, real-time, edge-to-cloud hybrid database for multi-modal workloads
Documentation 
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// SPDX-License-Identifier: BUSL-1.1

//! Collection-scoped scan quiesce primitive.
//!
//! Purpose: before unlinking on-disk files for a purged collection, every
//! in-flight scan against that collection must complete. An active TPC
//! scan dereferencing a freed mmap page faults the whole shard reactor —
//! a production crash, not a test flake. This module guarantees the
//! ordering: *stop accepting new scans → drain existing scans → unlink*.
//!
//! Split:
//! - [`refcount`] — per-`(tenant, collection)` scan refcount, `ScanGuard`
//!   RAII type, `try_start_scan` entry point.
//! - [`drain`] — `begin_drain` / `wait_until_drained` / `clear_drain`
//!   async drain coordination.
//!
//! The backing [`CollectionQuiesce`] is shared (Arc). Calls are rare
//! (one bump per scan, one drain per purge), so the internal `Mutex`
//! is not a hot-path bottleneck.

pub mod drain;
pub mod refcount;

pub use drain::WaitDrain;
pub use refcount::{CollectionQuiesce, ScanGuard, ScanStartError};