diff --git a/_constraints b/_constraints
index c6c8f92..5cefe32 100644
--- a/_constraints
+++ b/_constraints
@@ -2,22 +2,13 @@
 <constraints>
   <hardware>
     <disk>
-      <size unit="G">12</size>
+      <size unit="G">14</size>
     </disk>
     <memoryperjob>
-      <size unit="M">2000</size>
+      <size unit="M">1000</size>
     </memoryperjob>
+    <memory>
+      <size unit="G">4</size>
+    </memory>
   </hardware>
-  <overwrite>
-    <conditions>
-      <arch>armv6l</arch>
-      <arch>armv7l</arch>
-      <arch>aarch64</arch>
-    </conditions>
-    <hardware>
-      <memory>
-        <size unit="G">8</size>
-      </memory>
-    </hardware>
-  </overwrite>
 </constraints>
diff --git a/gnuradio.changes b/gnuradio.changes
index a7ac36e..92f2e39 100644
--- a/gnuradio.changes
+++ b/gnuradio.changes
@@ -1,3 +1,10 @@
+-------------------------------------------------------------------
+Wed Dec 28 10:04:35 UTC 2022 - Stefan Brüns <stefan.bruens@rwth-aachen.de>
+
+- Sanitize _constraints, 4GByte of memory is sufficient. Also,
+  2GByte memoryperjob rejects too many workers, so combine it
+  with %limit_build.
+
 -------------------------------------------------------------------
 Mon Dec 19 19:00:26 UTC 2022 - Wojciech Kazubski <wk@ire.pw.edu.pl>
 
diff --git a/gnuradio.spec b/gnuradio.spec
index 853fa7e..442b00c 100644
--- a/gnuradio.spec
+++ b/gnuradio.spec
@@ -56,6 +56,7 @@ BuildRequires:  libsndfile-devel
 BuildRequires:  libthrift-devel
 BuildRequires:  libusb-1_0-devel
 BuildRequires:  libxml2-devel
+BuildRequires:  memory-constraints
 BuildRequires:  ninja
 BuildRequires:  orc
 BuildRequires:  pkgconfig
@@ -182,6 +183,8 @@ This package contains some examples of using GNU Radio.
 find  gr-utils/modtool/templates/gr-newmod -name CMakeLists.txt -ls -exec mv '{}' '{}.tmpl' \;
 
 %build
+%limit_build -m 1500
+
 %define __builder ninja
 %cmake \
   -DENABLE_GRC=ON \