From cfda7d20bda1ecffe33235bc6c128ec90f35a02e Mon Sep 17 00:00:00 2001
From: Balint Reczey <balint.reczey@canonical.com>
Date: Fri, 30 Jun 2017 12:22:29 +0200
Subject: [PATCH] Use xz -T4 -0 instead of pxz

Test showed very little difference in file-size between -0 and -9 while
both compression and decompression need much less memory and compression
needs less CPU time for -0.

Supported xz versions before 5.2 also accept the -T4 option but ignore it.

Also depend on xz-utils instead of on pxz.

LP: #1701132
---
 debian/changelog                                   | 7 +++++--
 debian/control                                     | 2 +-
 live-build/auto/build                              | 2 +-
 live-build/ubuntu-cpc/hooks/040-qcow2-image.binary | 2 +-
 4 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/debian/changelog b/debian/changelog
index 08ff8068..142cfaa7 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -2,8 +2,11 @@ livecd-rootfs (2.448) UNRELEASED; urgency=medium
 
   [ Balint Reczey ]
   * Depend on packages in main instead of installing them at runtime
-  * Depend on pxz and vmdk-stream-converter instead of installing them
-    at run time
+  * Depend on vmdk-stream-converter instead of installing it at run time
+  * Use xz -T4 -0 instead of pxz (LP: #1701132)
+    Supported xz versions before 5.2 also accept the -T4 option but ignore
+    it.
+  * Depend on xz-utils instead of pxz
 
   [ Mathieu Trudel-Lapierre ]
   * auto/config: enable Debug::pkgDepCache::AutoInstall so tracking down
diff --git a/debian/control b/debian/control
index b2715e32..d54dd207 100644
--- a/debian/control
+++ b/debian/control
@@ -25,7 +25,6 @@ Depends: ${misc:Depends},
          lzma,
          parted,
          procps,
-         pxz,
          python-minimal | python,
          python3-software-properties,
          qemu-utils,
@@ -35,6 +34,7 @@ Depends: ${misc:Depends},
          sudo,
          ubuntu-image,
          vmdk-stream-converter [amd64 i386],
+         xz-utils,
          zerofree
 Suggests: partimage
 Breaks: ubuntu-defaults-builder (<< 0.32)
diff --git a/live-build/auto/build b/live-build/auto/build
index e909a00a..5c7b88ce 100755
--- a/live-build/auto/build
+++ b/live-build/auto/build
@@ -20,7 +20,7 @@ if [ "${IMAGEFORMAT:-}" = "ubuntu-image" ]; then
 	env SNAPPY_STORE_NO_CDN=1 \
 	ubuntu-image -c edge \
 		-o livecd."$PROJECT".img livecd."$PROJECT".model-assertion
-	pxz -T4 livecd."$PROJECT".img
+	xz -0 -T4 livecd."$PROJECT".img
 	exit 0
 fi
 
diff --git a/live-build/ubuntu-cpc/hooks/040-qcow2-image.binary b/live-build/ubuntu-cpc/hooks/040-qcow2-image.binary
index e98999c4..981f7bce 100755
--- a/live-build/ubuntu-cpc/hooks/040-qcow2-image.binary
+++ b/live-build/ubuntu-cpc/hooks/040-qcow2-image.binary
@@ -13,7 +13,7 @@ case $ARCH:$SUBARCH in
 	# Not sure if any other cloud images use subarch for something that
 	# should take qcow2 format, so only skipping this on raspi2 for now.
 	armhf:raspi2)
-		pxz -T4 -c binary/boot/disk.ext4 > livecd.ubuntu-cpc.disk1.img.xz
+		xz -0 -T4 -c binary/boot/disk.ext4 > livecd.ubuntu-cpc.disk1.img.xz
 	        exit 0
 		;;
 esac