diff --git a/_constraints b/_constraints
index 1036c6d..0e5b9e6 100644
--- a/_constraints
+++ b/_constraints
@@ -2,13 +2,10 @@
 <constraints>
   <hardware>
     <disk>
-      <size unit="G">13</size>
+      <size unit="G">9</size>
     </disk>
     <memory>
       <size unit="M">5700</size>
     </memory>
-    <memoryperjob>
-      <size unit="M">1600</size>
-    </memoryperjob>
   </hardware>
 </constraints>
diff --git a/opencv.changes b/opencv.changes
index 2d0484b..ab6e78c 100644
--- a/opencv.changes
+++ b/opencv.changes
@@ -1,3 +1,13 @@
+-------------------------------------------------------------------
+Mon Jan 10 11:08:32 UTC 2022 - Antonio Larrosa <alarrosa@suse.com>
+
+- Remove the memoryperjob constraint which doesn't work as one
+  would expect and breaks ppc64 builds.
+- Use %limit_memory -m 1700 to set the number of concurrent
+  jobs to a sane value and fix OOM errors when building in
+  workers with many cores.
+- Decrease the disk constraint to 9G which seems to be enough
+
 -------------------------------------------------------------------
 Sat Dec 25 17:43:11 UTC 2021 - Stefan Brüns <stefan.bruens@rwth-aachen.de>
 
diff --git a/opencv.spec b/opencv.spec
index 6bb7c0a..7edad92 100644
--- a/opencv.spec
+++ b/opencv.spec
@@ -51,6 +51,7 @@ BuildRequires:  cmake
 BuildRequires:  fdupes
 BuildRequires:  libeigen3-devel
 BuildRequires:  libjpeg-devel
+BuildRequires:  memory-constraints
 BuildRequires:  pkgconfig
 # OpenJPEGTargets.cmake erroneously requires the binaries
 BuildRequires:  openjpeg2
@@ -282,6 +283,8 @@ cp opencv_contrib-%{version}/LICENSE LICENSE.contrib
 rm -f doc/packaging.txt
 
 %build
+%limit_build -m 1700
+
 # openCV does not understand the standard RelWithDebinfo,
 #   but has a separate variable for it
 # Dynamic dispatch: https://github.com/opencv/opencv/wiki/CPU-optimizations-build-options