diff --git a/lib/debootstrap.sh b/lib/debootstrap.sh
index 127bfb71c3..5d0300c85f 100644
--- a/lib/debootstrap.sh
+++ b/lib/debootstrap.sh
@@ -773,8 +773,18 @@ create_image()
 		if [[ $COMPRESS_OUTPUTIMAGE == *xz* ]]; then
 			display_alert "Compressing" "${FINALDEST}/${version}.img.xz" "info"
 			# compressing consumes a lot of memory we don't have. Waiting for previous packing job to finish helps to run a lot more builds in parallel
-			[[ ${BUILD_ALL} == yes && $(free | grep Mem | awk '{print $4/$2 * 100.0}' | awk '{print int($1)}') -lt 5 ]] && while [[ $(ps -uax | grep "pixz" | wc -l) -gt 4 ]]; do echo -en "#"; sleep 20; done
-			pixz -8 -p 12 < $DESTIMG/${version}.img > ${FINALDEST}/${version}.img.xz
+			available_cpu=$(grep -c 'processor' /proc/cpuinfo)
+			[[ ${BUILD_ALL} == yes ]] && available_cpu=$(( $available_cpu * 30 / 100 )) # lets use 20% of resources in case of build-all
+			[[ ${available_cpu} -gt 8 ]] && available_cpu=8 # using more cpu cores for compressing is pointless
+			available_mem=$(LC_ALL=c free | grep Mem | awk '{print $4/$2 * 100.0}' | awk '{print int($1)}') # in percentage
+			# build optimisations when memory drops below 5%
+			if [[ ${BUILD_ALL} == yes && ${available_mem} -lt 15 ]]; then
+				while [[ $(ps -uax | grep "pixz" | wc -l) -gt 2 ]]
+					do echo -en "#"
+					sleep 20
+				done
+			fi
+			pixz -8 -p ${available_cpu} < $DESTIMG/${version}.img > ${FINALDEST}/${version}.img.xz
 			compression_type=".xz"
 		fi