feat: automate release workflow and add optional NUMA support

Refactor the Gitea release workflow to introduce a dedicated `create-release` job that exposes a shared release ID, eliminating redundant inline creation. Update the Makefile to automatically generate annotated tags with AI-derived markdown release notes from recent commits. Add an optional `numa` feature to `obikindex` that gates `hwlocality` behind conditional compilation, providing a graceful UMA fallback when disabled. Bump `obikmer` to v1.1.17.

.gitea/workflows/ci.yml

@@ -1,8 +1,9 @@
 name: CI
 
 on:
-  pull_request:
+  push:
     branches: ['main']
+  pull_request:
 
 jobs:
   build:

.gitea/workflows/release.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          fetch-depth: 0
+          fetch-tags: true
 
       - name: Create Gitea release
         id: create
@@ -86,11 +86,20 @@ jobs:
   build-macos-arm64:
     needs: create-release
     runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: src
     steps:
       - uses: actions/checkout@v4
 
-      - name: Login to registry
+      - name: Install Rust + zigbuild
-        run: echo "${{ secrets.REGISTRYTOKEN }}" | docker login registry.metabarcoding.org -u ${{ secrets.REGISTRYUSER }} --password-stdin
+        run: |
+          curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --default-toolchain stable
+          echo "$HOME/.cargo/bin" >> $GITHUB_PATH
+          sudo apt-get update -qq && sudo apt-get install -y -qq jq
+          pip install ziglang --quiet --break-system-packages
+          $HOME/.cargo/bin/cargo install cargo-zigbuild
+          $HOME/.cargo/bin/rustup target add aarch64-apple-darwin
 
       - name: Cache cargo registry
         uses: actions/cache@v4
@@ -103,12 +112,7 @@ jobs:
           restore-keys: macos-arm64-cargo-
 
       - name: Build macOS binary
-        run: |
+        run: cargo zigbuild --release --target aarch64-apple-darwin --no-default-features
-          docker run --rm \
-            -v "${{ github.workspace }}:/src" \
-            -w /src/src \
-            registry.metabarcoding.org/cibuilder/rustcrossosx:latest \
-            cargo build --release --target aarch64-apple-darwin --no-default-features
 
       - name: Prepare and upload artifact
         env:
@@ -116,7 +120,7 @@ jobs:
           RELEASE_ID: ${{ needs.create-release.outputs.release_id }}
         run: |
           mkdir -p /tmp/dist
-          cp src/target/aarch64-apple-darwin/release/obikmer /tmp/dist/obikmer-macos-arm64
+          cp target/aarch64-apple-darwin/release/obikmer /tmp/dist/obikmer-macos-arm64
           curl -s -X POST \
             "${{ github.server_url }}/api/v1/repos/${{ github.repository }}/releases/$RELEASE_ID/assets" \
             -H "Authorization: token $GITEA_TOKEN" \

.gitignore

@@ -8,7 +8,6 @@ data-stress
 *.pb
 ./**/*.json
 *.bin
-*.log
 Betula_exilis--IGA-24-33
 benchmark/genomes
 benchmark/simulated_data

Makefile

@@ -92,7 +92,6 @@ release: bump-version
 	git_hash=$$(jj log -r @ --no-graph -T 'commit_id'); \
 	commits=$$(jj log -r 'latest(tags())..@' --no-graph -T 'description ++ "\n"' 2>/dev/null || \
 	           jj log --no-graph -T 'description ++ "\n"' --limit 30); \
-	notes=$$(printf 'Write concise markdown release notes for obikmer (a Rust kmer genomics tool). Be technical and direct. Base them strictly on these commit messages:\n\n%s' "$$commits" | aichat 2>/dev/null); \
+	notes=$$(printf 'Write concise markdown release notes for obikmer (a Rust kmer genomics tool). Be technical and direct. Base them strictly on these commit messages:\n\n%s' "$$commits" | aichat); \
-	tag_msg="$${notes:-Release v$$new_version}"; \
+	git tag -a "v$$new_version" -m "$$notes" "$$git_hash" && \
-	git tag -a "v$$new_version" -m "$$tag_msg" "$$git_hash" && \
 	git push origin "v$$new_version"

docmd/architecture/numa_partition_runner.md

@@ -162,107 +162,14 @@ A single `PartitionRunner` instance can be built once per command invocation
 and reused across multiple `run()` calls (e.g. `merge` runs
 `merge_partitions` then `pack_matrices`).
 
-## Known issue: CPU-only activation signal stalls on I/O-bound stages
-
-Observed on a real `filter` run (109 genomes, 256 partitions, 8×24-core NUMA):
-`rebuild` (CPU-bound — k-mer construction) scales cleanly from 9 to 43 active
-workers as `CpuSample::do_i_activate` (`obisys::lib.rs`) sees efficiency climb.
-`pack_matrices` (I/O-bound — reopens and recomposes per-genome column files
-into `.pbmx`/`.pcmx`) activates one extra worker then flatlines at 10/192 for
-the rest of the stage, even though 256 partitions keep completing over several
-minutes. This matches the documented intent (§ Adaptive mechanism — "avoids
-over-provisioning ... I/O-bound ... workloads") but conflates two different
-things: *"CPU is not the bottleneck"* and *"more workers would not help"*. On
-storage with real queue depth (NVMe, RAID, parallel FS) the second stage could
-still benefit from more concurrent workers even with flat CPU usage — a signal
-the current mechanism cannot see.
-
-A one-off artefact was also found in the same log: right after a stage
-transition, `do_i_activate` produced a physically impossible spike (efficiency
-~94 cores on a 192-core box) because it has no minimum-window guard — unlike
-its sibling `cpu_efficiency`, which returns `0.0` if `wall < 0.1s`
-(`obisys::lib.rs:260`). `do_i_activate` unconditionally overwrites
-`self.wall`/`self.user_secs`/`self.sys_secs` even when the elapsed window is
-too short to be meaningful, so a burst of rapid completions right after
-activating a worker can divide a real CPU delta by a near-zero wall delta.
-
-### Implemented: I/O signal + shared debounce guard
-
-`IoSample` (`obisys::lib.rs`, alongside `CpuSample`) is fed by
-`read_bytes`/`write_bytes` from `/proc/self/io` on Linux (actual bytes
-submitted to the block layer — not `rchar`/`wchar`, which also count
-page-cache hits, and not `ru_inblock`/`ru_oublock`, unreliable on macOS), with
-a `proc_pid_rusage(RUSAGE_INFO_V4)` fallback on macOS
-(`ri_diskio_bytesread`/`ri_diskio_byteswritten`, FFI only via `libc`, no new
-dependency — same pattern as the existing `getrusage` bindings). Any other
-target degrades gracefully to a signal that never triggers (falls back to
-CPU-only activation), same pattern as `cgroup_v2_available`.
-
-`maybe_activate` (`numa.rs`) activates a worker if *either* signal still shows
-headroom, making `PartitionRunner` adapt to whichever resource is actually the
-bottleneck without per-call configuration. Both samplers are called
-unconditionally — no `||` short-circuit — so neither window starves behind
-whichever signal fires first:
-
-```rust
-let cpu_wants_more = cpu_sample.do_i_activate(CPU_SPAWN_THRESHOLD);
-let io_wants_more  = io_sample.do_i_activate(IO_SPAWN_THRESHOLD);
-if cpu_wants_more || io_wants_more {
-    activate_tx.send(()).ok();
-    ...
-}
-```
-
-Unlike the CPU signal (an absolute delta in cores — a bounded, portable unit),
-raw I/O throughput has no natural scale across devices, so `IoSample` uses a
-**relative** growth threshold instead of an absolute one:
-
-```rust
-pub fn do_i_activate(&mut self, threshold: f64) -> bool {
-    let elapsed = self.wall.elapsed().as_secs_f64();
-    if elapsed < 0.1 { return false; }        // state untouched — window keeps accumulating
-
-    let n = Self::read_bytes();
-    let rate = n.saturating_sub(self.bytes) as f64 / elapsed;
-    let activate = if self.previous_rate == 0.0 {
-        rate > 0.0                            // bootstrap: any measured throughput is signal
-    } else {
-        (rate - self.previous_rate) / self.previous_rate >= threshold
-    };
-
-    self.bytes = n;
-    self.wall  = Instant::now();              // reset only on a real sample
-    activate
-}
-```
-
-The `elapsed < 0.1s → return false without mutating state` guard was also
-back-ported into `CpuSample::do_i_activate` (previously missing — source of
-the ~94-core artefact above) — one fix for both problems, and it removes the
-need for any arbitrary I/O-rate floor: a short/noisy window is rejected
-outright rather than papered over with a hardware-dependent constant.
-
-Both spawn thresholds (`CPU_SPAWN_THRESHOLD`, `IO_SPAWN_THRESHOLD`, both `0.2`)
-are defined as `const` in `PartitionRunner::run` (`numa.rs`). The I/O value is
-a starting point, not a derived one — needs empirical validation against a
-real `pack` run.
-
-Starting threshold: `0.2` (20 % relative growth) for `IoSample`, same order of
-magnitude as the CPU threshold's *implicit* relative sensitivity (in the
-observed log, an 8→9 worker step raised efficiency by ~12 %). This is a
-starting point, not a derived value — I/O throughput is lumpier than CPU time
-(buffered writes flush in bursts), so it needs empirical validation against a
-real `pack` run before being considered final.
-
 ## Open questions
 
 - **Error handling**: `run` currently returns the first error; remaining errors
   are dropped.  A `Vec<E>` return would give complete diagnostics.
 
 - **`workers_per_node` tuning**: currently `(cpus / 8).max(3).min(8)`, calibrated
-  for merge on BeeGFS.  Superseded by the I/O signal above for the "more
+  for merge on BeeGFS.  I/O-bound commands (`dump`, `select`) may benefit from
-  workers would help despite flat CPU" case — a per-call override may still be
+  a higher value.  A per-call override could be added to the API.
-  worth keeping as a manual escape hatch.
 
 - **`on_done` ordering**: the runner serialises calls to `on_done` via an
   internal `Arc<Mutex<C>>`.  `Send` is required (the Arc clone crosses thread

src/Cargo.lock

@@ -1704,7 +1704,7 @@ dependencies = [
 
 [[package]]
 name = "obikmer"
-version = "1.1.33"
+version = "1.1.17"
 dependencies = [
  "clap",
  "csv",

src/obikindex/src/numa.rs

@@ -20,7 +20,7 @@ use hwlocality::cpu::binding::CpuBindingFlags;
 use hwlocality::cpu::cpuset::CpuSet;
 #[cfg(feature = "numa")]
 use hwlocality::object::types::ObjectType;
-use obisys::{CpuSample, IoSample};
+use obisys::CpuSample;
 use tracing::debug;
 
 // ── Public interface ──────────────────────────────────────────────────────────
@@ -190,13 +190,10 @@ impl PartitionRunner {
     /// Run `f(i)` for every index in `order`.
     ///
     /// Workers are pre-spawned dormant and activated adaptively. A timer thread
-    /// fires an efficiency check every `TIMER_SECS` seconds; each completed
+    /// fires a CPU-efficiency check every `TIMER_SECS` seconds; each completed
     /// partition resets that timer (forcing an immediate check) and also
-    /// triggers its own inline check. A new worker is activated whenever CPU
+    /// triggers its own inline check. A new worker is activated whenever
-    /// efficiency grows by at least `CPU_SPAWN_THRESHOLD` (absolute, in cores)
+    /// efficiency falls below `SPAWN_THRESHOLD`.
-    /// or I/O throughput grows by at least `IO_SPAWN_THRESHOLD` (relative) since
-    /// the last check — whichever resource is the actual bottleneck still shows
-    /// headroom.
     ///
     /// `on_done(i, result, elapsed)` is called from the controller thread as
     /// each partition completes — suitable for progress bars and result
@@ -220,9 +217,12 @@ impl PartitionRunner {
             return Ok(());
         }
 
-        const CPU_SPAWN_THRESHOLD: f64 = 0.2;
+        const SPAWN_THRESHOLD: f64 = 0.95;
-        const IO_SPAWN_THRESHOLD:  f64 = 0.2;
+        const TIMER_SECS:      u64 = 30;
-        const TIMER_SECS:          u64 = 30;
+
+        let n_cores = std::thread::available_parallelism()
+            .map(|n| n.get())
+            .unwrap_or(1);
 
         // ── Channels ──────────────────────────────────────────────────────────
         let (part_tx,     part_rx)     = unbounded::<usize>();
@@ -287,12 +287,11 @@ impl PartitionRunner {
             drop(event_tx);
 
             // ── Controller ────────────────────────────────────────────────────
-            let initial_workers = n_nodes.min(max_workers).min(n_total);
+            activate_tx.send(()).ok();
-            for _ in 0..initial_workers { activate_tx.send(()).ok(); }
+            let mut n_active              = 1usize;
-            let mut n_active   = initial_workers;
+            let mut cpu_sample            = CpuSample::now();
-            let mut cpu_sample = CpuSample::now();
+            let mut eff_at_last_spawn     = 0.0f64; // 0 = no previous spawn to evaluate
-            let mut io_sample  = IoSample::now();
+            let mut completed             = 0usize;
-            let mut completed  = 0usize;
 
             while completed < n_total {
                 let Ok(event) = event_rx.recv() else { break };
@@ -308,17 +307,15 @@ impl PartitionRunner {
                         // Inline check: same logic as a timer tick.
                         maybe_activate(
                             &activate_tx, &mut n_active, max_workers,
-                            &mut cpu_sample, CPU_SPAWN_THRESHOLD,
+                            &mut cpu_sample, &mut eff_at_last_spawn,
-                            &mut io_sample, IO_SPAWN_THRESHOLD,
+                            n_cores, SPAWN_THRESHOLD, completed, n_total,
-                            completed, n_total,
                         );
                     }
                     WorkerEvent::TimerTick => {
                         maybe_activate(
                             &activate_tx, &mut n_active, max_workers,
-                            &mut cpu_sample, CPU_SPAWN_THRESHOLD,
+                            &mut cpu_sample, &mut eff_at_last_spawn,
-                            &mut io_sample, IO_SPAWN_THRESHOLD,
+                            n_cores, SPAWN_THRESHOLD, completed, n_total,
-                            completed, n_total,
                         );
                     }
                 }
@@ -345,27 +342,42 @@ enum WorkerEvent<R, E> {
 }
 
 fn maybe_activate(
-    activate_tx:   &crossbeam_channel::Sender<()>,
+    activate_tx:         &crossbeam_channel::Sender<()>,
-    n_active:      &mut usize,
+    n_active:            &mut usize,
-    max_workers:   usize,
+    max_workers:         usize,
-    cpu_sample:    &mut CpuSample,
+    cpu_sample:          &mut CpuSample,
-    cpu_threshold: f64,
+    eff_at_last_spawn:   &mut f64,
-    io_sample:     &mut IoSample,
+    n_cores:             usize,
-    io_threshold:  f64,
+    threshold:           f64,
-    completed:     usize,
+    completed:           usize,
-    n_total:       usize,
+    n_total:             usize,
 ) {
     if *n_active >= max_workers || completed >= n_total { return; }
 
-    // Call both unconditionally (no `||` short-circuit): each sampler must
+    let eff = cpu_sample.cpu_efficiency(n_cores);
-    // advance its own window every tick, regardless of what the other one
+    if eff >= threshold { return; }  // CPU already saturated
-    // reports, or it would starve behind whichever signal fires first.
-    let cpu_wants_more = cpu_sample.do_i_activate(cpu_threshold);
-    let io_wants_more  = io_sample.do_i_activate(io_threshold);
 
-    if cpu_wants_more || io_wants_more {
+    // Check that the previous activation was beneficial enough.
+    // Going from k-1 → k workers, the minimum acceptable speedup is (k-1+0.2)/(k-1).
+    // For the very first extra worker (n_active == 1, no previous spawn), skip this
+    // check: eff_at_last_spawn == 0 acts as the sentinel.
+    let last_spawn_was_beneficial = if *eff_at_last_spawn < 1e-9 {
+        true  // first additional worker: no prior data to evaluate
+    } else {
+        let k_before   = (*n_active - 1) as f64;
+        let min_speedup = (k_before + 0.2) / k_before;
+        let actual_speedup = eff / *eff_at_last_spawn;
+        actual_speedup >= min_speedup
+    };
+
+    if last_spawn_was_beneficial {
         activate_tx.send(()).ok();
+        *eff_at_last_spawn = eff;
         *n_active += 1;
-        debug!("activated worker {}/{}", n_active, max_workers);
+        *cpu_sample = CpuSample::now();
+        debug!(
+            "activated worker {}/{} — efficiency {:.0}%",
+            n_active, max_workers, eff * 100.0,
+        );
     }
 }

src/obikmer/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "obikmer"
-version = "1.1.33"
+version = "1.1.17"
 edition = "2024"
 
 [[bin]]
@@ -18,7 +18,7 @@ obikrope      = { path = "../obikrope" }
 obikpartitionner = { path = "../obikpartitionner" }
 obisys        = { path = "../obisys" }
 obiskio       = { path = "../obiskio" }
-obikindex     = { path = "../obikindex", default-features = false }
+obikindex     = { path = "../obikindex" }
 obitaxonomy   = { path = "../obitaxonomy" }
 obilayeredmap = { path = "../obilayeredmap" }
 clap          = { version = "4", features = ["derive"] }
@@ -33,6 +33,4 @@ tracing-subscriber = { version = "0.3", features = ["fmt", "env-filter"] }
 pprof = { version = "0.13", features = ["prost-codec"], optional = true }
 
 [features]
-default   = ["numa"]
-numa      = ["obikindex/numa"]
 profiling = ["dep:pprof"]

src/obisys/src/lib.rs

@@ -4,7 +4,7 @@ use std::sync::{Condvar, Mutex};
 use std::time::{Duration, Instant};
 
 use indicatif::{ProgressBar, ProgressStyle};
-use tracing::{debug, info, warn};
+use tracing::{info, warn};
 
 const BRAILLE: &[&str] = &["⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏"];
 
@@ -14,25 +14,24 @@ const BRAILLE: &[&str] = &["⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧
 /// a TTY (e.g. HPC job logs): every 10% for bounded bars, every ~10 s for
 /// spinners (throttled on `set_message`).
 pub struct TracedBar {
-    pb: ProgressBar,
+    pb:          ProgressBar,
-    label: String,
+    label:       String,
-    unit: String,
+    unit:        String,
-    total: u64,             // 0 for spinners
+    total:       u64,        // 0 for spinners
-    start: Instant,         // creation time, for spinner throttling
+    start:       Instant,    // creation time, for spinner throttling
-    last_pct: AtomicU64,    // last emitted 10%-bucket (1..=10), 0 = none yet
+    last_pct:    AtomicU64,  // last emitted 10%-bucket (1..=10), 0 = none yet
-    last_log_ms: AtomicU64, // ms since `start` at last spinner log
+    last_log_ms: AtomicU64,  // ms since `start` at last spinner log
 }
 
 impl TracedBar {
     pub fn inc(&self, delta: u64) {
         self.pb.inc(delta);
         if self.pb.is_hidden() && self.total > 0 {
-            let pos = self.pb.position();
+            let pos   = self.pb.position();
             let pct10 = (pos * 10) / self.total; // 0..=10
-            let last = self.last_pct.load(Ordering::Relaxed);
+            let last  = self.last_pct.load(Ordering::Relaxed);
             if pct10 > last
-                && self
+                && self.last_pct
-                    .last_pct
                     .compare_exchange(last, pct10, Ordering::Relaxed, Ordering::Relaxed)
                     .is_ok()
             {
@@ -50,14 +49,14 @@ impl TracedBar {
         let msg = msg.into();
         if self.pb.is_hidden() {
             if self.total > 0 {
-                debug!(stage = %self.label, "{msg}");
+                // bounded bar: always log (already rate-limited by 10% threshold in inc)
+                info!(stage = %self.label, "{msg}");
             } else {
                 // spinner: throttle to ~10 s
                 let now_ms = self.start.elapsed().as_millis() as u64;
-                let last = self.last_log_ms.load(Ordering::Relaxed);
+                let last   = self.last_log_ms.load(Ordering::Relaxed);
                 if now_ms >= last + 10_000
-                    && self
+                    && self.last_log_ms
-                        .last_log_ms
                         .compare_exchange(last, now_ms, Ordering::Relaxed, Ordering::Relaxed)
                         .is_ok()
                 {
@@ -84,13 +83,8 @@ pub fn spinner(label: &str) -> TracedBar {
     );
     pb.enable_steady_tick(Duration::from_millis(100));
     TracedBar {
-        pb,
+        pb, label: label.to_string(), unit: String::new(), total: 0,
-        label: label.to_string(),
+        start: Instant::now(), last_pct: AtomicU64::new(0), last_log_ms: AtomicU64::new(0),
-        unit: String::new(),
-        total: 0,
-        start: Instant::now(),
-        last_pct: AtomicU64::new(0),
-        last_log_ms: AtomicU64::new(0),
     }
 }
 
@@ -107,13 +101,8 @@ pub fn progress_bar(label: &str, n: u64, unit: &str) -> TracedBar {
     );
     pb.enable_steady_tick(Duration::from_millis(100));
     TracedBar {
-        pb,
+        pb, label: label.to_string(), unit: unit.to_string(), total: n,
-        label: label.to_string(),
+        start: Instant::now(), last_pct: AtomicU64::new(0), last_log_ms: AtomicU64::new(0),
-        unit: unit.to_string(),
-        total: n,
-        start: Instant::now(),
-        last_pct: AtomicU64::new(0),
-        last_log_ms: AtomicU64::new(0),
     }
 }
 
@@ -215,19 +204,13 @@ fn tv_to_secs(tv: timeval) -> f64 {
 }
 
 #[cfg(target_os = "macos")]
-fn rss_to_bytes(ru: &rusage) -> u64 {
+fn rss_to_bytes(ru: &rusage) -> u64 { ru.ru_maxrss as u64 }
-    ru.ru_maxrss as u64
-}
 
 #[cfg(not(target_os = "macos"))]
-fn rss_to_bytes(ru: &rusage) -> u64 {
+fn rss_to_bytes(ru: &rusage) -> u64 { ru.ru_maxrss as u64 * 1024 }
-    ru.ru_maxrss as u64 * 1024
-}
 
 // Monotonically increasing counters — negative delta would be a kernel bug.
-fn delta(end: i64, start: i64) -> u64 {
+fn delta(end: i64, start: i64) -> u64 { (end - start).max(0) as u64 }
-    (end - start).max(0) as u64
-}
 
 // ── CpuSample ─────────────────────────────────────────────────────────────────
 
@@ -235,151 +218,31 @@ fn delta(end: i64, start: i64) -> u64 {
 /// Use [`cpu_efficiency`](Self::cpu_efficiency) to measure the fraction of
 /// available cores used since the snapshot was taken.
 pub struct CpuSample {
-    wall: Instant,
+    wall:      Instant,
     user_secs: f64,
-    sys_secs: f64,
+    sys_secs:  f64,
-    previous: f64,
 }
 
 impl CpuSample {
     pub fn now() -> Self {
         let ru = get_rusage();
         Self {
-            wall: Instant::now(),
+            wall:      Instant::now(),
             user_secs: tv_to_secs(ru.ru_utime),
-            sys_secs: tv_to_secs(ru.ru_stime),
+            sys_secs:  tv_to_secs(ru.ru_stime),
-            previous: 0.0,
         }
     }
 
     /// (user_delta + sys_delta) / (wall_delta × n_cores) since this snapshot.
     /// Returns 0.0 if less than 100 ms have elapsed (too noisy).
     pub fn cpu_efficiency(&self, n_cores: usize) -> f64 {
-        let ru = get_rusage();
+        let ru   = get_rusage();
         let wall = self.wall.elapsed().as_secs_f64();
-        if wall < 0.1 {
+        if wall < 0.1 { return 0.0; }
-            return 0.0;
+        let cpu = (tv_to_secs(ru.ru_utime) - self.user_secs)
-        }
+                + (tv_to_secs(ru.ru_stime) - self.sys_secs);
-        let cpu =
-            (tv_to_secs(ru.ru_utime) - self.user_secs) + (tv_to_secs(ru.ru_stime) - self.sys_secs);
         cpu / (wall * n_cores as f64)
     }
-
-    pub fn do_i_activate(&mut self, threshold: f64) -> bool {
-        let delta_wall = self.wall.elapsed().as_secs_f64();
-        if delta_wall < 0.1 {
-            // Window too short to be meaningful — leave state untouched so it
-            // keeps accumulating until a real sample can be taken.
-            return false;
-        }
-
-        let n = CpuSample::now();
-        let delta_ru = (n.user_secs - self.user_secs) + (n.sys_secs - self.sys_secs);
-
-        let efficiency = delta_ru / delta_wall;
-        let activate = 0f64.max(efficiency - self.previous) >= threshold;
-
-        debug!(
-            "Do I activate : {} -> {} = {} Activate: {}",
-            self.previous,
-            efficiency,
-            0f64.max(efficiency - self.previous),
-            activate
-        );
-        self.previous = efficiency;
-        self.user_secs = n.user_secs;
-        self.sys_secs = n.sys_secs;
-        self.wall = n.wall;
-
-        activate
-    }
-}
-
-// ── IoSample ──────────────────────────────────────────────────────────────────
-
-/// Snapshot of process-wide block I/O (bytes read + written) + wall clock.
-///
-/// Same activation protocol as [`CpuSample`], but the growth check in
-/// [`do_i_activate`](Self::do_i_activate) is *relative* rather than absolute:
-/// raw I/O throughput has no portable scale across storage devices, unlike a
-/// core count.
-pub struct IoSample {
-    wall: Instant,
-    bytes: u64,
-    previous_rate: f64,
-}
-
-impl IoSample {
-    pub fn now() -> Self {
-        Self {
-            wall: Instant::now(),
-            bytes: Self::read_bytes(),
-            previous_rate: 0.0,
-        }
-    }
-
-    /// Bytes actually submitted to the block layer (read + write), summed
-    /// process-wide. Returns 0 if unavailable — degrades gracefully to a
-    /// signal that never triggers activation (CPU-only heuristic).
-    #[cfg(target_os = "linux")]
-    fn read_bytes() -> u64 {
-        let Ok(io) = std::fs::read_to_string("/proc/self/io") else {
-            return 0;
-        };
-        io.lines()
-            .filter_map(|l| {
-                l.strip_prefix("read_bytes: ")
-                    .or_else(|| l.strip_prefix("write_bytes: "))
-            })
-            .filter_map(|v| v.trim().parse::<u64>().ok())
-            .sum()
-    }
-
-    #[cfg(target_os = "macos")]
-    fn read_bytes() -> u64 {
-        use libc::{RUSAGE_INFO_V4, getpid, proc_pid_rusage, rusage_info_v4};
-        let mut info: rusage_info_v4 = unsafe { std::mem::zeroed() };
-        let ret =
-            unsafe { proc_pid_rusage(getpid(), RUSAGE_INFO_V4, &mut info as *mut _ as *mut _) };
-        if ret != 0 {
-            return 0;
-        }
-        info.ri_diskio_bytesread + info.ri_diskio_byteswritten
-    }
-
-    #[cfg(not(any(target_os = "linux", target_os = "macos")))]
-    fn read_bytes() -> u64 {
-        0
-    }
-
-    /// Same protocol as [`CpuSample::do_i_activate`] (0.1 s minimum window,
-    /// state untouched on early return), but growth is measured relative to
-    /// the previous rate. `threshold` is a fraction, e.g. `0.2` for a 20 %
-    /// increase in throughput since the last real sample.
-    pub fn do_i_activate(&mut self, threshold: f64) -> bool {
-        let elapsed = self.wall.elapsed().as_secs_f64();
-        if elapsed < 0.1 {
-            return false;
-        }
-
-        let n = Self::read_bytes();
-        let rate = n.saturating_sub(self.bytes) as f64 / elapsed;
-        let activate = if self.previous_rate == 0.0 {
-            rate > 0.0 // bootstrap: any measured throughput is signal enough
-        } else {
-            (rate - self.previous_rate) / self.previous_rate >= threshold
-        };
-
-        debug!(
-            "Do I activate (I/O) : {} -> {} Activate: {}",
-            self.previous_rate, rate, activate
-        );
-        self.previous_rate = rate;
-        self.bytes = n;
-        self.wall = Instant::now();
-
-        activate
-    }
 }
 
 // ── public API ────────────────────────────────────────────────────────────────
@@ -388,37 +251,33 @@ impl IoSample {
 #[must_use = "call .stop() to record the stage"]
 pub struct Stage {
     label: String,
-    wall: Instant,
+    wall:  Instant,
-    ru: rusage,
+    ru:    rusage,
 }
 
 impl Stage {
     pub fn start(label: impl Into<String>) -> Self {
         let label = label.into();
         info!(stage = %label, "started");
-        Self {
+        Self { label, wall: Instant::now(), ru: get_rusage() }
-            label,
-            wall: Instant::now(),
-            ru: get_rusage(),
-        }
     }
 
     pub fn stop(self) -> StageStats {
         let wall_secs = self.wall.elapsed().as_secs_f64();
         let end = get_rusage();
         let stats = StageStats {
-            label: self.label,
+            label:         self.label,
             wall_secs,
-            user_secs: tv_to_secs(end.ru_utime) - tv_to_secs(self.ru.ru_utime),
+            user_secs:     tv_to_secs(end.ru_utime) - tv_to_secs(self.ru.ru_utime),
-            sys_secs: tv_to_secs(end.ru_stime) - tv_to_secs(self.ru.ru_stime),
+            sys_secs:      tv_to_secs(end.ru_stime) - tv_to_secs(self.ru.ru_stime),
             max_rss_bytes: rss_to_bytes(&end),
-            minor_faults: delta(end.ru_minflt as i64, self.ru.ru_minflt as i64),
+            minor_faults:  delta(end.ru_minflt  as i64, self.ru.ru_minflt  as i64),
-            major_faults: delta(end.ru_majflt as i64, self.ru.ru_majflt as i64),
+            major_faults:  delta(end.ru_majflt  as i64, self.ru.ru_majflt  as i64),
-            vol_ctx: delta(end.ru_nvcsw as i64, self.ru.ru_nvcsw as i64),
+            vol_ctx:       delta(end.ru_nvcsw   as i64, self.ru.ru_nvcsw   as i64),
-            invol_ctx: delta(end.ru_nivcsw as i64, self.ru.ru_nivcsw as i64),
+            invol_ctx:     delta(end.ru_nivcsw  as i64, self.ru.ru_nivcsw  as i64),
-            in_blocks: delta(end.ru_inblock as i64, self.ru.ru_inblock as i64),
+            in_blocks:     delta(end.ru_inblock as i64, self.ru.ru_inblock as i64),
-            out_blocks: delta(end.ru_oublock as i64, self.ru.ru_oublock as i64),
+            out_blocks:    delta(end.ru_oublock as i64, self.ru.ru_oublock as i64),
-            swaps: delta(end.ru_nswap as i64, self.ru.ru_nswap as i64),
+            swaps:         delta(end.ru_nswap   as i64, self.ru.ru_nswap   as i64),
         };
         info!(
             stage      = %stats.label,
@@ -440,30 +299,27 @@ impl Stage {
 
 /// Per-stage efficiency metrics collected from `getrusage(RUSAGE_SELF)` deltas.
 pub struct StageStats {
-    pub label: String,
+    pub label:         String,
-    pub wall_secs: f64,
+    pub wall_secs:     f64,
-    pub user_secs: f64,
+    pub user_secs:     f64,
-    pub sys_secs: f64,
+    pub sys_secs:      f64,
     /// Peak RSS at end of stage (bytes). ru_maxrss is a process-lifetime maximum,
     /// so this reflects the high-water mark up to and including this stage.
     pub max_rss_bytes: u64,
-    pub minor_faults: u64,
+    pub minor_faults:  u64,
-    pub major_faults: u64,
+    pub major_faults:  u64,
-    pub vol_ctx: u64,    // voluntary context switches
+    pub vol_ctx:       u64,   // voluntary context switches
-    pub invol_ctx: u64,  // involuntary context switches
+    pub invol_ctx:     u64,   // involuntary context switches
-    pub in_blocks: u64,  // filesystem block reads (after page cache)
+    pub in_blocks:     u64,   // filesystem block reads (after page cache)
-    pub out_blocks: u64, // filesystem block writes
+    pub out_blocks:    u64,   // filesystem block writes
-    pub swaps: u64,
+    pub swaps:         u64,
 }
 
 impl StageStats {
     /// (user + sys) / wall — effective thread count utilisation.
     pub fn parallelism(&self) -> f64 {
-        if self.wall_secs > 1e-9 {
+        if self.wall_secs > 1e-9 { (self.user_secs + self.sys_secs) / self.wall_secs }
-            (self.user_secs + self.sys_secs) / self.wall_secs
+        else { 0.0 }
-        } else {
-            0.0
-        }
     }
 
     /// parallelism / n_cores — fraction of available CPU power used (0..1+).
@@ -479,33 +335,25 @@ pub struct Reporter {
 }
 
 impl Reporter {
-    pub fn new() -> Self {
+    pub fn new() -> Self { Self::default() }
-        Self::default()
+    pub fn push(&mut self, stats: StageStats) { self.stages.push(stats); }
-    }
+    pub fn stages(&self) -> &[StageStats] { &self.stages }
-    pub fn push(&mut self, stats: StageStats) {
-        self.stages.push(stats);
-    }
-    pub fn stages(&self) -> &[StageStats] {
-        &self.stages
-    }
     /// Print the summary to stderr.
-    pub fn print(&self) {
+    pub fn print(&self) { eprint!("{self}"); }
-        eprint!("{self}");
-    }
 }
 
 // ── diagnosis ─────────────────────────────────────────────────────────────────
 
 struct Diagnosis {
-    tag: &'static str,
+    tag:    &'static str,
     detail: Option<String>,
 }
 
 // Thresholds are intentionally conservative to avoid false positives.
 fn diagnose(s: &StageStats, n_cores: usize) -> Diagnosis {
-    let eff = s.efficiency(n_cores);
+    let eff     = s.efficiency(n_cores);
     let cpu_pct = eff * 100.0;
-    let io_ops = s.in_blocks + s.out_blocks;
+    let io_ops  = s.in_blocks + s.out_blocks;
 
     // swaps > 0 is the only reliable cross-platform indicator of true RAM exhaustion.
     // ru_majflt is intentionally excluded: on macOS it counts all file-backed mmap
@@ -539,43 +387,26 @@ fn diagnose(s: &StageStats, n_cores: usize) -> Diagnosis {
             )),
         };
     }
-    Diagnosis {
+    Diagnosis { tag: "—", detail: None }
-        tag: "—",
-        detail: None,
-    }
 }
 
 // ── display helpers ───────────────────────────────────────────────────────────
 
 fn fmt_secs(s: f64) -> String {
-    if s >= 100.0 {
+    if s >= 100.0     { format!("{:.0}s",  s) }
-        format!("{:.0}s", s)
+    else if s >= 10.0 { format!("{:.1}s",  s) }
-    } else if s >= 10.0 {
+    else if s >= 1.0  { format!("{:.2}s",  s) }
-        format!("{:.1}s", s)
+    else              { format!("{:.0}ms", s * 1000.0) }
-    } else if s >= 1.0 {
-        format!("{:.2}s", s)
-    } else {
-        format!("{:.0}ms", s * 1000.0)
-    }
 }
 
 fn fmt_bytes(b: u64) -> String {
-    if b >= 1 << 30 {
+    if b >= 1 << 30      { format!("{:.1} GB", b as f64 / (1u64 << 30) as f64) }
-        format!("{:.1} GB", b as f64 / (1u64 << 30) as f64)
+    else if b >= 1 << 20 { format!("{:.0} MB", b as f64 / (1u64 << 20) as f64) }
-    } else if b >= 1 << 20 {
+    else                 { format!("{:.0} KB", b as f64 / 1024.0) }
-        format!("{:.0} MB", b as f64 / (1u64 << 20) as f64)
-    } else {
-        format!("{:.0} KB", b as f64 / 1024.0)
-    }
 }
 
 fn fmt_efficiency(par: f64, n_cores: usize) -> String {
-    format!(
+    format!("{:.1}×/{} ({:.0}%)", par, n_cores, par / n_cores as f64 * 100.0)
-        "{:.1}×/{} ({:.0}%)",
-        par,
-        n_cores,
-        par / n_cores as f64 * 100.0
-    )
 }
 
 // ── Display ───────────────────────────────────────────────────────────────────
@@ -583,8 +414,8 @@ fn fmt_efficiency(par: f64, n_cores: usize) -> String {
 // ── MemoryBudget ──────────────────────────────────────────────────────────────
 
 struct BudgetInner {
-    remaining: u64,
+    remaining:   u64,
-    active: usize,
+    active:      usize,
     peak_active: usize,
 }
 
@@ -594,8 +425,8 @@ struct BudgetInner {
 /// completion. Non-deadlock guarantee: when no worker is active the next
 /// acquire always succeeds regardless of cost vs. remaining budget.
 pub struct MemoryBudget {
-    total: u64,
+    total:   u64,
-    inner: Mutex<BudgetInner>,
+    inner:   Mutex<BudgetInner>,
     condvar: Condvar,
 }
 
@@ -603,11 +434,7 @@ impl MemoryBudget {
     pub fn new(total: u64) -> Self {
         Self {
             total,
-            inner: Mutex::new(BudgetInner {
+            inner:   Mutex::new(BudgetInner { remaining: total, active: 0, peak_active: 0 }),
-                remaining: total,
-                active: 0,
-                peak_active: 0,
-            }),
             condvar: Condvar::new(),
         }
     }
@@ -616,9 +443,9 @@ impl MemoryBudget {
         let mut g = self.inner.lock().unwrap();
         loop {
             if g.active == 0 || g.remaining >= cost {
-                g.remaining = g.remaining.saturating_sub(cost);
+                g.remaining     = g.remaining.saturating_sub(cost);
-                g.active += 1;
+                g.active       += 1;
-                g.peak_active = g.peak_active.max(g.active);
+                g.peak_active   = g.peak_active.max(g.active);
                 return;
             }
             g = self.condvar.wait(g).unwrap();
@@ -628,66 +455,47 @@ impl MemoryBudget {
     pub fn release(&self, cost: u64) {
         let mut g = self.inner.lock().unwrap();
         g.remaining = (g.remaining + cost).min(self.total);
-        g.active -= 1;
+        g.active   -= 1;
         self.condvar.notify_all();
     }
 
-    pub fn total(&self) -> u64 {
+    pub fn total(&self)       -> u64   { self.total }
-        self.total
+    pub fn active(&self)      -> usize { self.inner.lock().unwrap().active }
-    }
+    pub fn remaining(&self)   -> u64   { self.inner.lock().unwrap().remaining }
-    pub fn active(&self) -> usize {
+    pub fn peak_active(&self) -> usize { self.inner.lock().unwrap().peak_active }
-        self.inner.lock().unwrap().active
-    }
-    pub fn remaining(&self) -> u64 {
-        self.inner.lock().unwrap().remaining
-    }
-    pub fn peak_active(&self) -> usize {
-        self.inner.lock().unwrap().peak_active
-    }
 }
 
 // ── Display ───────────────────────────────────────────────────────────────────
 
 impl fmt::Display for Reporter {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        if self.stages.is_empty() {
+        if self.stages.is_empty() { return Ok(()); }
-            return Ok(());
-        }
 
         let n_cores = std::thread::available_parallelism()
             .map(|n| n.get())
             .unwrap_or(1);
 
         // column widths
-        let nw = self
+        let nw = self.stages.iter().map(|s| s.label.len()).max().unwrap_or(5).max(5);
-            .stages
-            .iter()
-            .map(|s| s.label.len())
-            .max()
-            .unwrap_or(5)
-            .max(5);
         // efficiency col: worst-case width for this run's n_cores value
         let ew = format!("{:.1}×/{} (100%)", 99.9f64, n_cores).len();
 
         let sep_w = nw + 2 + 7 + 2 + ew + 2 + 8 + 2 + 12;
-        let sep = "─".repeat(sep_w);
+        let sep   = "─".repeat(sep_w);
 
         // header
-        writeln!(
+        writeln!(f, "{:<nw$}  {:>7}  {:>ew$}  {:>8}  status",
-            f,
+            "stage", "wall", "efficiency", "peak RSS")?;
-            "{:<nw$}  {:>7}  {:>ew$}  {:>8}  status",
-            "stage", "wall", "efficiency", "peak RSS"
-        )?;
         writeln!(f, "{sep}")?;
 
         // compute all diagnoses up front (needed for both table and footnotes)
-        let diagnoses: Vec<Diagnosis> = self.stages.iter().map(|s| diagnose(s, n_cores)).collect();
+        let diagnoses: Vec<Diagnosis> = self.stages.iter()
+            .map(|s| diagnose(s, n_cores))
+            .collect();
 
         // per-stage rows
         for (s, d) in self.stages.iter().zip(diagnoses.iter()) {
-            writeln!(
+            writeln!(f, "{:<nw$}  {:>7}  {:>ew$}  {:>8}  {}",
-                f,
-                "{:<nw$}  {:>7}  {:>ew$}  {:>8}  {}",
                 s.label,
                 fmt_secs(s.wall_secs),
                 fmt_efficiency(s.parallelism(), n_cores),
@@ -697,21 +505,14 @@ impl fmt::Display for Reporter {
         }
 
         // totals
-        let tw = self.stages.iter().map(|s| s.wall_secs).sum::<f64>();
+        let tw   = self.stages.iter().map(|s| s.wall_secs).sum::<f64>();
-        let tu = self.stages.iter().map(|s| s.user_secs).sum::<f64>();
+        let tu   = self.stages.iter().map(|s| s.user_secs).sum::<f64>();
-        let ts = self.stages.iter().map(|s| s.sys_secs).sum::<f64>();
+        let ts   = self.stages.iter().map(|s| s.sys_secs).sum::<f64>();
-        let trss = self
+        let trss = self.stages.iter().map(|s| s.max_rss_bytes).max().unwrap_or(0);
-            .stages
-            .iter()
-            .map(|s| s.max_rss_bytes)
-            .max()
-            .unwrap_or(0);
         let tpar = if tw > 1e-9 { (tu + ts) / tw } else { 0.0 };
 
         writeln!(f, "{sep}")?;
-        writeln!(
+        writeln!(f, "{:<nw$}  {:>7}  {:>ew$}  {:>8}",
-            f,
-            "{:<nw$}  {:>7}  {:>ew$}  {:>8}",
             "TOTAL",
             fmt_secs(tw),
             fmt_efficiency(tpar, n_cores),
@@ -719,9 +520,7 @@ impl fmt::Display for Reporter {
         )?;
 
         // bottleneck footnotes (only if at least one anomaly detected)
-        let bottlenecks: Vec<(&str, &str)> = self
+        let bottlenecks: Vec<(&str, &str)> = self.stages.iter()
-            .stages
-            .iter()
             .zip(diagnoses.iter())
             .filter_map(|(s, d)| d.detail.as_deref().map(|det| (s.label.as_str(), det)))
             .collect();