[pkg] fix: optimize compression operations

This tries to use threaded programs for auxilliary
compressions and decompressions. Replacing xz
should have the largest impact - not only it is
now threaded, but the compression level is also
dropped sigificantly.

Fixes https://github.com/ev3dev-lang-java/openjdk-ev3/issues/59

Author: JakubVanek

packaging/Dockerfile

@@ -13,7 +13,8 @@ RUN apt-get -qq update && \
         devscripts debhelper fakeroot \
         zip unzip \
         gnupg dctrl-tools dput \
-        liblcms2-2
+        liblcms2-2 \
+        pigz xz-utils
 
 # prepare a nonroot user
 COPY compiler.sudoers /etc/sudoers.d/compiler

packaging/package.sh

@@ -53,9 +53,9 @@ PKGDIR="/build/pkg/$PKGNAME"
 rm -rf "/build/pkg"
 mkdir "/build/pkg"
 cd "/build/pkg"
-tar -xf "/build/jri-${DEB_JRI_PLATFORM}.tar.gz" -C "/build/pkg"
+tar -x -I 'pigz' -f "/build/jri-${DEB_JRI_PLATFORM}.tar.gz" -C "/build/pkg"
 mv "/build/pkg/jri" "$PKGDIR"
-tar -cJf "$PKGDIR.orig.tar.xz" "$PKGNAME"
+tar -c -I 'xz -T0 -1' -f "$PKGDIR.orig.tar.xz" "$PKGNAME"
 cp -rf /opt/jdkpkg/debian "$PKGDIR"
 cd "$PKGDIR"