diff --git a/desktop/src-tauri/crates/buzz-terminal/src/reader.rs b/desktop/src-tauri/crates/buzz-terminal/src/reader.rs index 4dc4aa46c..438267627 100644 --- a/desktop/src-tauri/crates/buzz-terminal/src/reader.rs +++ b/desktop/src-tauri/crates/buzz-terminal/src/reader.rs @@ -112,14 +112,19 @@ impl Feeder { /// exactly how a paused reader strands a child mid-teardown; a reader that /// simply stops asking resumes by default. /// - /// **Not yet consumed in production.** The runtime reader pumps - /// [`Feeder::drain`] to completion after every read, so the tail cannot - /// currently grow to the cap and nothing needs to ask. This signal exists - /// for the reader that stops pumping -- it is the queue bound, and the - /// pump loop is the only reason the queue bound is not load-bearing - /// today. Stated rather than left to be inferred from an empty - /// call-graph: an unused signal that looks wired is worse than one that - /// says it isn't. + /// **No production consumer today, and not an oversight.** The runtime + /// reader pumps [`Feeder::drain`] to completion after every read + /// (`terminal_runtime.rs`), so the tail is empty between iterations and + /// this can never go true -- measured 0 bytes high-water against 1 MiB of + /// pure RIS, the densest atom there is. It exists for a future reader + /// that defers pumping, and such a reader **must** consult it: without + /// the pump loop the same stream reaches [`TAIL_CAP`] in 257 reads of + /// 16 KiB. + /// + /// The numbers are here rather than "nothing calls this" because the + /// signal and the loop are one fact from two sides. Delete the loop and + /// this predicate stops being unreachable in the same instant it starts + /// being needed. pub fn tail_full(&self) -> bool { self.pending_bytes() >= TAIL_CAP }