From 773af06b5a35ed16bce62ac01449a7887feee9c3 Mon Sep 17 00:00:00 2001
From: "James E. Blair" <jim@acmegating.com>
Date: Thu, 15 Feb 2024 16:18:51 -0800
Subject: [PATCH] Reduce unit test concurrency

This reduces the unit test concurrency to 75% of available cpus.
This appears to reduce the chances of racy test failures while
increasing the job runtime in opendev from 50m to 1h.

Change-Id: I90a22dbe8d28fc35d609f8dbc63305b501c544e6
---
 noxfile.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/noxfile.py b/noxfile.py
index 30058cef78..d8f35f6ea3 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -91,7 +91,7 @@ def tests(session):
     session.install('-e', '.')
     session.run_always('tools/yarn-build.sh', external=True)
     session.run_always('zuul-manage-ansible', '-v')
-    procs = max(int(multiprocessing.cpu_count() - 1), 1)
+    procs = max(int(multiprocessing.cpu_count() * 0.75), 1)
     session.run('stestr', 'run', '--slowest', f'--concurrency={procs}',
                 *session.posargs)