From 2f1c57e0ae5a9e9aedb3a5acbbeecae1c7ee1769 Mon Sep 17 00:00:00 2001
From: Stewart Allen <stewart.allen@gmail.com>
Date: Wed, 4 Mar 2026 21:28:32 -0500
Subject: [PATCH] raise concurrency cap for multi-cpu systems

---
 src/geo/slicer.js               |  4 ++--
 src/kiri/mode/fdm/work/slice.js |  8 ++++++++
 src/kiri/run/minion.js          | 19 ++++++++++++-------
 src/kiri/run/worker.js          | 22 ++++++++++++----------
 4 files changed, 34 insertions(+), 19 deletions(-)

diff --git a/src/geo/slicer.js b/src/geo/slicer.js
index 4889a8cb..9254ec69 100644
--- a/src/geo/slicer.js
+++ b/src/geo/slicer.js
@@ -41,6 +41,7 @@ export async function slice(points, options = {}) {
         zSum = 0.0,             // sanity check that points enclose non-zere volume
         buckets = [],           // banded/grouped faces to speed up slice/search
         overlapMax = options.overlap || 0.75,
+        bucketMin = options.bucketMin ?? 1,
         bucketMax = options.bucketMax || 100,
         onupdate = options.onupdate || function() {},
         sliceFn = dval(options.slicer, sliceZ),
@@ -138,7 +139,7 @@ export async function slice(points, options = {}) {
     let zSpan = zMax - zMin;
     let zSpanAvg = zSum / points.length;
     let bucketCount = options.bucket !== false ?
-        Math.min(bucketMax, Math.max(1, Math.floor(zSpan / zSpanAvg))) : 1;
+        Math.min(bucketMax, Math.max(bucketMin, Math.floor(zSpan / zSpanAvg))) : 1;
 
     zScale = 1 / (zMax / bucketCount);
 
@@ -211,7 +212,6 @@ export async function slice(points, options = {}) {
         let count = 0;
         let opt = { ...options, zMin, zMax, zIndexes };
         let ps = [];
-
         for (let i = 0, l = buckets.length; i < l; i++) {
             let bucket = buckets[i];
             let { points, slices } = bucket;
diff --git a/src/kiri/mode/fdm/work/slice.js b/src/kiri/mode/fdm/work/slice.js
index 1dafe0aa..3756d3f7 100644
--- a/src/kiri/mode/fdm/work/slice.js
+++ b/src/kiri/mode/fdm/work/slice.js
@@ -318,6 +318,10 @@ export function sliceOne(settings, widget, onupdate, ondone) {
         }
     }
 
+    if (isConcurrent) {
+        minions.setPoints(points);
+    }
+
     // create Slice objects for specified list of Z heights
     // zGen() produces the list (or empty for slicer auto-detected)
     slice(points, {
@@ -326,6 +330,7 @@ export function sliceOne(settings, widget, onupdate, ondone) {
         xray: process.xray,
         zMin: bounds.min.z,
         zMax: bounds.max.z - zCut,
+        bucketMin: minions.concurrent * 5,
         union: controller.healMesh,
         indices: process.indices || process.xray,
         useAssembly,
@@ -351,6 +356,9 @@ export function sliceOne(settings, widget, onupdate, ondone) {
     })
     .then(decodeSlices)
     .then(processSlices)
+    .then(() => {
+        minions.setPoints([]);
+    })
     .then(ondone);
 
     // z index generator (bottom up)
diff --git a/src/kiri/run/minion.js b/src/kiri/run/minion.js
index 0a229558..22cf938b 100644
--- a/src/kiri/run/minion.js
+++ b/src/kiri/run/minion.js
@@ -154,14 +154,11 @@ const funcs = self.minion = {
 
     sliceZ(data, seq) {
         debug('minion.sliceZ', { data, seq });
-        let { z, points, options } = data;
-        let i = 0, p = 0, realp = new Array(points.length / 3);
-        while (i < points.length) {
-            realp[p++] = newPoint(points[i++], points[i++], points[i++]).round(3);
-        }
+        let { z, options } = data;
+        let { points } = cache;
         let state = { zero: [] };
         let output = [];
-        sliceZ(z, realp, {
+        sliceZ(z, points, {
             ...options,
             each(out) { output.push(out) }
         }).then(() => {
@@ -173,9 +170,17 @@ const funcs = self.minion = {
         });
     },
 
+    setPoints(data, seq) {
+        let { points } = data;
+        let i = 0, p = 0, realp = new Array(points.length / 3);
+        while (i < points.length) {
+            realp[p++] = newPoint(points[i++], points[i++], points[i++]).round(3);
+        }
+        cache.points = realp;
+    },
+
     putCache(msg) {
         const { key, data } = msg;
-        // log({ minion_putCache: key, data });
         if (data) {
             cache[key] = data;
         } else {
diff --git a/src/kiri/run/worker.js b/src/kiri/run/worker.js
index 34594561..83c6620a 100644
--- a/src/kiri/run/worker.js
+++ b/src/kiri/run/worker.js
@@ -39,7 +39,7 @@ let drivers = {
         WJET
     },
     ccvalue = self.navigator ? self.navigator.hardwareConcurrency || 0 : 0,
-    concurrent = Math.min(4, self.Worker && ccvalue > 3 ? ccvalue - 1 : 0),
+    concurrent = Math.round(Math.max(4, self.Worker && ccvalue > 3 ? ccvalue * 0.75 : 0)),
     current = {
         print: null,
         snap: null,
@@ -174,6 +174,16 @@ const minwork = {
         }
     },
 
+    setPoints(points) {
+        let i = 0, floatP = new Float32Array(points.length * 3);
+        for (let p of points) {
+            floatP[i++] = p.x;
+            floatP[i++] = p.y;
+            floatP[i++] = p.z;
+        }
+        minwork.broadcast("setPoints", { points: floatP });
+    },
+
     // added functions (should be namespaced)
 
     subtract({ a, b, outA, outB, z, area, wasm }) {
@@ -285,17 +295,9 @@ const minwork = {
                 reject("concurrent slice unavaiable");
             }
             let { each } = options;
-            // todo use shared array buffer?
-            let i = 0, floatP = new Float32Array(points.length * 3);
-            for (let p of points) {
-                floatP[i++] = p.x;
-                floatP[i++] = p.y;
-                floatP[i++] = p.z;
-            }
             minwork.queue({
                 cmd: "sliceZ",
                 z,
-                points: floatP,
                 options: codec.toCodable(options)
             }, data => {
                 let recs = codec.decode(data.output);
@@ -305,7 +307,7 @@ const minwork = {
                     }
                 }
                 resolve(recs);
-            }, [ floatP.buffer ]);
+            });
         });
     },
 };