diff --git a/petsc.spec b/petsc.spec
index 14f7b92..3b0ab88 100644
--- a/petsc.spec
+++ b/petsc.spec
@@ -661,6 +661,10 @@ pushd %{name}-%{version}
 ##
 
 RPM_BUILD_NCPUS="`%{_bindir}/getconf _NPROCESSORS_ONLN`"
+%ifarch %{arm}
+# Likely running out of memory during build
+[ $RPM_BUILD_NCPUS -gt 3 ] && RPM_BUILD_NCPUS=3
+%endif
 make \
  V=1 MAKE_NP=$RPM_BUILD_NCPUS PETSC_DIR=%{_builddir}/%{name}-%{version}/%{name}-%{version} PETSC_ARCH=%{_arch} all
 popd