diff --git a/memory-constraints.changes b/memory-constraints.changes
index 4d8f3bf..48a899c 100644
--- a/memory-constraints.changes
+++ b/memory-constraints.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Sat Jun 15 14:34:00 UTC 2019 - Stefan Brüns <stefan.bruens@rwth-aachen.de>
+
+- Take SwapTotal into account, MemTotal only reflects physical memory. Some
+  workers have a considerable amount of swap.
+
 -------------------------------------------------------------------
 Sat Apr  7 14:57:25 UTC 2018 - tchvatal@suse.com
 
diff --git a/memory-constraints.macros b/memory-constraints.macros
index 8cb2ca7..e06c46a 100644
--- a/memory-constraints.macros
+++ b/memory-constraints.macros
@@ -16,10 +16,11 @@
     echo "System jobs: $_threads" \
     if test "$_threads" -gt 1 ; then \
         mem_per_process="$_core_memory" \
-        max_mem=$(awk '/MemTotal/ { print $2 }' /proc/meminfo) \
-        max_jobs="$(($max_mem / ($mem_per_process * 1000)))" \
+        max_physmem=$(awk '/MemTotal/ { print $2 }' /proc/meminfo) \
+        max_swapmem=$(awk '/SwapTotal/ { print $2 }' /proc/meminfo) \
+        max_jobs="$((($max_physmem + $max_swapmem) / ($mem_per_process * 1000)))" \
         test "$_threads" -gt "$max_jobs" && _threads="$max_jobs" && echo "Warning: Reducing number of jobs to $max_jobs because of memory limits" \
-        test "$_threads" -le 0 && $_threads=1 && echo "Warning: Do not use the parallel build at all because of memory limits" \
+        test "$_threads" -le 0 && _threads=1 && echo "Warning: Do not use the parallel build at all because of memory limits" \
     fi \
     %global jobs $([[ -n $_threads ]] && echo $_threads || echo "`/usr/bin/getconf _NPROCESSORS_ONLN`") \
     %global _smp_mflags $([[ -n $_threads ]] && echo "-j$_threads" || echo "-j`/usr/bin/getconf _NPROCESSORS_ONLN`") \