Improve parallelism limits in build-workspace yarn pack

Signed-off-by: Eric Peterson <ericpeterson@spotify.com>

.changeset/cli-melancholy-in-advance.md

@@ -0,0 +1,5 @@
+---
+'@backstage/cli': patch
+---
+
+The packing process when running `build-workspace` with the `--alwaysYarnPack` flag now respects the `BACKSTAGE_CLI_BUILD_PARALLEL` environment variable, defaulting parallel work limits based on CPU availability.

packages/cli/package.json

@@ -130,7 +130,6 @@
     "node-libs-browser": "^2.2.1",
     "npm-packlist": "^5.0.0",
     "ora": "^5.3.0",
-    "p-limit": "^3.1.0",
     "p-queue": "^6.6.2",
     "pirates": "^4.0.6",
     "postcss": "^8.1.0",

packages/cli/src/lib/packager/createDistWorkspace.ts

@@ -21,7 +21,6 @@ import {
   resolve as resolvePath,
   relative as relativePath,
 } from 'path';
-import pLimit from 'p-limit';
 import { tmpdir } from 'os';
 import tar, { CreateOptions, FileOptions } from 'tar';
 import partition from 'lodash/partition';
@@ -369,11 +368,10 @@ async function moveToDistWorkspace(
   }
 
   // Repacking in parallel is much faster and safe for all packages outside of the Backstage repo
-  // Limit concurrency to 10 to avoid resource exhaustion on larger monorepos.
-  const limit = pLimit(10);
-  await Promise.all(
-    safePackages.map((target, index) =>
-      limit(() => pack(target, `temp-package-${index}.tgz`)),
-    ),
-  );
+  await runParallelWorkers({
+    items: safePackages.map((target, index) => ({ target, index })),
+    worker: async ({ target, index }) => {
+      await pack(target, `temp-package-${index}.tgz`);
+    },
+  });
 }

yarn.lock

@@ -4020,7 +4020,6 @@ __metadata:
     nodemon: ^3.0.1
     npm-packlist: ^5.0.0
     ora: ^5.3.0
-    p-limit: ^3.1.0
     p-queue: ^6.6.2
     pirates: ^4.0.6
     postcss: ^8.1.0