From 463f30ccfbaff07d642076fce688c86eaa3baec6 Mon Sep 17 00:00:00 2001
From: Zoltan Kochan <z@kochan.io>
Date: Fri, 21 Nov 2025 15:29:56 +0100
Subject: [PATCH] perf: increase the default network concurrency on machines
 with many CPU cores (#10215)

close #10068
---
 .changeset/small-results-hunt.md                      | 7 +++++++
 pkg-manager/package-requester/src/packageRequester.ts | 8 ++------
 worker/src/index.ts                                   | 2 +-
 3 files changed, 10 insertions(+), 7 deletions(-)
 create mode 100644 .changeset/small-results-hunt.md

diff --git a/.changeset/small-results-hunt.md b/.changeset/small-results-hunt.md
new file mode 100644
index 0000000000..0f75272f93
--- /dev/null
+++ b/.changeset/small-results-hunt.md
@@ -0,0 +1,7 @@
+---
+"@pnpm/package-requester": minor
+"@pnpm/worker": minor
+"pnpm": minor
+---
+
+Increase the network concurrency on machines with many CPU cores. We pick a network concurrency that is not less than 16 and not more than 64 and it is calculated by the number of pnpm workers multiplied by 3 [#10068](https://github.com/pnpm/pnpm/issues/10068).
diff --git a/pkg-manager/package-requester/src/packageRequester.ts b/pkg-manager/package-requester/src/packageRequester.ts
index 0e0c369935..bc0544300e 100644
--- a/pkg-manager/package-requester/src/packageRequester.ts
+++ b/pkg-manager/package-requester/src/packageRequester.ts
@@ -1,5 +1,4 @@
 import { createReadStream, promises as fs } from 'fs'
-import os from 'os'
 import path from 'path'
 import {
   getFilePathByModeInCafs as _getFilePathByModeInCafs,
@@ -44,7 +43,7 @@ import {
 } from '@pnpm/store-controller-types'
 import { type DependencyManifest, type SupportedArchitectures } from '@pnpm/types'
 import { depPathToFilename } from '@pnpm/dependency-path'
-import { readPkgFromCafs as _readPkgFromCafs } from '@pnpm/worker'
+import { calcMaxWorkers, readPkgFromCafs as _readPkgFromCafs } from '@pnpm/worker'
 import { familySync } from 'detect-libc'
 import PQueue from 'p-queue'
 import pDefer from 'p-defer'
@@ -111,10 +110,7 @@ export function createPackageRequester (
   } {
   opts = opts || {}
 
-  // A lower bound of 16 is enforced to prevent performance degradation,
-  // especially in CI environments. Tests with a threshold lower than 16
-  // have shown consistent underperformance.
-  const networkConcurrency = opts.networkConcurrency ?? Math.max(os.availableParallelism?.() ?? os.cpus().length, 16)
+  const networkConcurrency = opts.networkConcurrency ?? Math.min(64, Math.max(calcMaxWorkers() * 3, 16))
   const requestsQueue = new PQueue({
     concurrency: networkConcurrency,
   })
diff --git a/worker/src/index.ts b/worker/src/index.ts
index 41e638df04..879e1a8a6c 100644
--- a/worker/src/index.ts
+++ b/worker/src/index.ts
@@ -52,7 +52,7 @@ function createTarballWorkerPool (): WorkerPool {
   return workerPool
 }
 
-function calcMaxWorkers () {
+export function calcMaxWorkers (): number {
   if (process.env.PNPM_MAX_WORKERS) {
     return parseInt(process.env.PNPM_MAX_WORKERS)
   }