diff --git a/_constraints b/_constraints
index 419aa3f..240290e 100644
--- a/_constraints
+++ b/_constraints
@@ -1,5 +1,8 @@
 <constraints>
     <hardware>
+      <physicalmemory>
+        <size unit="G">3</size>
+      </physicalmemory>
       <disk>
         <size unit="G">12</size>
       </disk>
diff --git a/vtk.changes b/vtk.changes
index 9c8343b..fff46e3 100644
--- a/vtk.changes
+++ b/vtk.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Wed Jun 10 12:57:24 UTC 2020 - Guillaume GARDET <guillaume.gardet@opensuse.org>
+
+- Update _constraints to avoid OOM errors
+
 -------------------------------------------------------------------
 Sun May 31 20:28:03 UTC 2020 - Atri Bhattacharya <badshah400@gmail.com>
 
diff --git a/vtk.spec b/vtk.spec
index 13c795f..d119200 100644
--- a/vtk.spec
+++ b/vtk.spec
@@ -39,7 +39,7 @@
 %endif
 
 # PEGTL IN LEAP 15.1 IS TOO OLD (< 2.0.0)
-# cmake STILL CHECKS FOR JAVAH (AND CHEATING WITH %{_bindir}/true NO LONGER WORKS)
+# cmake STILL CHECKS FOR JAVAH (AND CHEATING WITH {_bindir}/true NO LONGER WORKS)
 %if 0%{?suse_version} == 1500 && 0%{?sle_version} == 150100
 %bcond_with    java
 %bcond_with    pegtl