From 5da4c93ef25cc8154aa2d93742362cca95a06418 Mon Sep 17 00:00:00 2001
From: Martin Kroeker <martin@ruby.chemie.uni-freiburg.de>
Date: Wed, 27 Mar 2024 20:34:55 +0100
Subject: [PATCH] Cap the number of parallel threads

---
 interface/lapack/getrf.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/interface/lapack/getrf.c b/interface/lapack/getrf.c
index 323370ebc..7d1f6bc70 100644
--- a/interface/lapack/getrf.c
+++ b/interface/lapack/getrf.c
@@ -95,14 +95,19 @@ int NAME(blasint *M, blasint *N, FLOAT *a, blasint *ldA, blasint *ipiv, blasint
 
 #ifdef SMP
   args.common = NULL;
+
 #ifndef DOUBLE
-  if (args.m*args.n < 40000)
-#else
-  if (args.m*args.n < 10000)
-#endif
-	args.nthreads=1;
-  else
-	args.nthreads = num_cpu_avail(4);
+  int nmax = 40000;
+#else 
+  int nmax = 10000;
+endif
+  if (args.m*args.n <nmax) {
+    args.nthreads = 1;
+  } else {
+    args.nthreads = num_cpu_avail(4);
+    if ((args.m*args.n)/args.nthreads <nmax)
+	    args.nthreads = (args.m*args.n)/nmax;
+  }
 
   if (args.nthreads == 1) {
 #endif