From ffe4ecfc037cfb2f9b7d700f9887034a080f8848 Mon Sep 17 00:00:00 2001
From: Cristy <urban-warrior@imagemagick.org>
Date: Sat, 9 Aug 2025 20:02:55 -0400
Subject: [PATCH] don't thread for modest numbers of image tiles

---
 coders/ashlar.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/coders/ashlar.c b/coders/ashlar.c
index 8d2b638f22..9124cb61e3 100644
--- a/coders/ashlar.c
+++ b/coders/ashlar.c
@@ -53,13 +53,14 @@
 #include "MagickCore/list.h"
 #include "MagickCore/magick.h"
 #include "MagickCore/memory_.h"
+#include "MagickCore/module.h"
 #include "MagickCore/option.h"
 #include "MagickCore/property.h"
 #include "MagickCore/quantum-private.h"
 #include "MagickCore/static.h"
 #include "MagickCore/string_.h"
 #include "MagickCore/string-private.h"
-#include "MagickCore/module.h"
+#include "MagickCore/thread-private.h"
 #include "MagickCore/utility.h"
 #include "MagickCore/xwindow.h"
 #include "MagickCore/xwindow-private.h"
@@ -625,7 +626,8 @@ static Image *ASHLARImage(ImageInfo *image_info,Image *image,
   extent.width=0;
   extent.height=0;
 #if defined(MAGICKCORE_OPENMP_SUPPORT)
-  #pragma omp parallel for schedule(dynamic) shared(status,extent)
+  #pragma omp parallel for schedule(dynamic) shared(status,extent) \
+    magick_number_threads(image,image,n,1)
 #endif
   for (i=0; i < n; i++)
   {