tricu

preview-compare.mjs (2773B)

---

 // Compare the same 128-node unary tree: no sharing/expansion advantage hidden
 // in the baseline. Every iteration checks the complete shape in either format.
 import assert from 'node:assert/strict';
 import {readFile,writeFile} from 'node:fs/promises';
 import {spawnSync} from 'node:child_process';
 import {createHash} from 'node:crypto';
 import {cpus} from 'node:os';
 import {WasmRuntime} from './runtime.mjs';
 import {Graph} from '../demo-site/dist/graph.js';
 const [wasmPath,output,mode,pressureArg]=process.argv.slice(2);
 const tree='1'.repeat(127)+'0',iterations=100;
 if(mode) {
   const pressure=Number(pressureArg);
   const g=mode==='js'?new Graph({fuel:Infinity}):await WasmRuntime.create(await readFile(wasmPath));
   const root=g.fromTernary(tree);
   // Extra owned roots simulate a retained host session. JS has no root-table
   // scan in this path, but retain equivalent host references for comparison.
   const retained=Array.from({length:pressure},()=>mode==='js'?g.leaf:g.retain(g.leaf));
   const before=mode==='js'?null:g.stats().owned;
   const start=performance.now();
   for(let i=0;i<iterations;i++) {
     if(mode==='wasm-batch') {
       const p=g.preview(root,128);
       assert.equal(p.truncated,false);assert.equal(p.nodes.length,128);
       for(let j=0;j<128;j++)assert.deepEqual(p.nodes[j],{id:j,kind:j===127?'leaf':'stem',children:j===127?[]:[j+1]});
     } else assert.equal(g.toTernary(root),tree);
   }
   const ms=performance.now()-start;
   if(mode!=='js')assert.equal(g.stats().owned,before);
   assert.equal(retained.length,pressure);
   console.log(JSON.stringify({mode,pressure,iterations,ms,perSnapshotMs:ms/iterations,peakRssKiB:process.resourceUsage().maxRSS}));
   g.dispose?.();
 } else {
   const samples=[];
   for(const pressure of [0,2000])for(let round=0;round<3;round++) {
     for(const mode of round%2?['wasm-batch','wasm-node','js']:['js','wasm-node','wasm-batch']) {
       const child=spawnSync(process.execPath,[import.meta.filename,wasmPath,'-',mode,String(pressure)],{encoding:'utf8',timeout:60_000});
       if(child.error||child.status!==0)throw new Error(`${mode}: ${child.error??child.stderr}`);
       samples.push({...JSON.parse(child.stdout),round});
     }
   }
   await writeFile(output,JSON.stringify({schema:1,node:process.version,cpu:cpus()[0]?.model,
     wasmSha256:createHash('sha256').update(await readFile(wasmPath)).digest('hex'),tree, samples},null,2)+'\n');
   for(const pressure of [0,2000]) {
     const median=mode=>samples.filter(s=>s.mode===mode&&s.pressure===pressure).map(s=>s.perSnapshotMs).sort((a,b)=>a-b)[1];
     console.log(`128-node inspection (${pressure} extra roots): JS ${median('js').toFixed(3)} ms; WASM/node ${median('wasm-node').toFixed(3)} ms; WASM/batch ${median('wasm-batch').toFixed(3)} ms`);
   }
 }