Rebuild: strings that outlive their chunk are copied (worker 1.14 → 0.66 GB)

A slice of a chunk's text keeps the whole text alive (tens of MB) for as
long as the file it belongs to stays open: message-ids, file details and
cache keys are now copies. edge:bench on boneless: peak RSS 1,137 → ~660
MB, external memory 570 → 40–75 MB, the same speed (~190k headers/s);
the same results on 800k real lines. edge:bench prints the breakdown.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

commands/edge_bench.ts

@@ -97,6 +97,7 @@ export default class EdgeBench extends BaseCommand {
     let compressed = 0
     let text = 0
     let peakRss = 0
+    let peakDetail = ''
     const out = { headers: 0, releases: 0, files: 0, segments: 0, payload: 0, candidates: 0, fragments: 0, samples: 0 }
     const counts = new Map<string, number>()
     const keys = new Set<string>()
@@ -156,14 +157,18 @@ export default class EdgeBench extends BaseCommand {
       out.fragments += batch.fragments.length
       out.samples += batch.samples.length
       for (const c of batch.counts) counts.set(`${c.rule} ${c.key}`.trim(), (counts.get(`${c.rule} ${c.key}`.trim()) ?? 0) + c.articles)
-      peakRss = Math.max(peakRss, process.memoryUsage().rss)
+      const m = process.memoryUsage()
+      if (m.rss > peakRss) {
+        peakRss = m.rss
+        peakDetail = `heap ${(m.heapUsed / 1e6).toFixed(0)}/${(m.heapTotal / 1e6).toFixed(0)} MB, external ${(m.external / 1e6).toFixed(0)} MB, array buffers ${(m.arrayBuffers / 1e6).toFixed(0)} MB`
+      }
     }
     const cpu = process.cpuUsage(cpuStart)
     const cpuS = (cpu.user + cpu.system) / 1e6
     const total = t.inflate + t.parse + t.index
     this.logger.info(`${group} ${start}–${end}: ${files.length} chunks, ${(compressed / 1e6).toFixed(0)} MB compressed, ${(text / 1e6).toFixed(0)} MB text`)
     this.logger.info(`${out.headers.toLocaleString('en')} headers in ${(total / 1000).toFixed(1)} s (${Math.round(out.headers / (total / 1000)).toLocaleString('en')}/s on one core; CPU ${cpuS.toFixed(1)} s, wall ${((Date.now() - wall) / 1000).toFixed(1)} s)`)
-    this.logger.info(`  inflate ${(t.inflate / 1000).toFixed(1)} s, parse ${(t.parse / 1000).toFixed(1)} s, index ${(t.index / 1000).toFixed(1)} s; peak RSS ${(peakRss / 1e6).toFixed(0)} MB`)
+    this.logger.info(`  inflate ${(t.inflate / 1000).toFixed(1)} s, parse ${(t.parse / 1000).toFixed(1)} s, index ${(t.index / 1000).toFixed(1)} s; peak RSS ${(peakRss / 1e6).toFixed(0)} MB (${peakDetail})`)
     this.logger.info(`  ${batches} batches of ${this.batchChunks} chunks: ${out.releases} release chunks for ${keys.size} releases (${(out.releases / Math.max(1, keys.size)).toFixed(2)} chunks per release)`)
     this.logger.info(`  kept: ${out.releases} release chunks, ${out.files} files, ${out.segments} segments, payload ${(out.payload / 1e6).toFixed(1)} MB (${(out.payload / Math.max(1, out.segments)).toFixed(1)} B/segment); ${out.candidates} candidates, ${out.fragments} fragments, ${out.samples} samples`)
     for (const [k, v] of [...counts].sort((a, b) => b[1] - a[1]).slice(0, 8)) this.logger.info(`  dropped ${k}: ${v.toLocaleString('en')} articles`)