From c7bbf9c987a0473aafbd8a4f48ed07cd52fccc38 Mon Sep 17 00:00:00 2001
From: Andrew <16061801+brada4@users.noreply.github.com>
Date: Sat, 20 Oct 2018 11:13:29 +0300
Subject: [PATCH] Attempt to tame _hemv threading #1820

---
 interface/zhemv.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/interface/zhemv.c b/interface/zhemv.c
index d1996ad69..8995ca1c2 100644
--- a/interface/zhemv.c
+++ b/interface/zhemv.c
@@ -195,7 +195,12 @@ void CNAME(enum CBLAS_ORDER order, enum CBLAS_UPLO Uplo, blasint n, void *VALPHA
   buffer = (FLOAT *)blas_memory_alloc(1);
 
 #ifdef SMP
-  nthreads = num_cpu_avail(2);
+  // see graph in issue #1820 for explanation and room for improvement
+  if (n<362) {
+	  nthreads = 1 ;
+  } else {
+  	  nthreads = num_cpu_avail(2);
+  };
 
   if (nthreads == 1) {
 #endif