From c24ceea4b1315f79ae26618191d2c193ee9fab01 Mon Sep 17 00:00:00 2001
From: Thomas Kaiser <github@kaiser-edv.de>
Date: Thu, 6 Sep 2018 21:56:51 +0200
Subject: [PATCH] Allow also RAMLOG_ALGORITHM to be defined with zram

---
 .../usr/lib/armbian/armbian-zram-config       | 25 ++++++++++++-------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/packages/bsp/common/usr/lib/armbian/armbian-zram-config b/packages/bsp/common/usr/lib/armbian/armbian-zram-config
index 7463f35999..eb77aa4c0a 100755
--- a/packages/bsp/common/usr/lib/armbian/armbian-zram-config
+++ b/packages/bsp/common/usr/lib/armbian/armbian-zram-config
@@ -8,7 +8,8 @@
 
 # Functions:
 #
-# activate_zram
+# activate_zram_swap
+# activate_ramlog_partition
 
 
 # Read in basic OS image information
@@ -16,13 +17,13 @@
 # and script configuration
 . /usr/lib/armbian/armbian-common
 
-# ZRAM_PERCENTAGE, ZRAM_MAX_DEVICES and SWAP_ALGORITHM can be defined there:
+# ZRAM_PERCENTAGE, ZRAM_MAX_DEVICES, SWAP_ALGORITHM and RAMLOG_ALGORITHM can be defined:
 [ -f /etc/default/armbian-zram-config ] && . /etc/default/armbian-zram-config
 
 activate_zram_swap() {
-
 	# Do not interfere with already present config-zram package
 	dpkg -l | grep -q 'zram-config' && exit 0
+
 	[[ "$ENABLED" != "true" ]] && exit 0
 
 	# Load zram module with n instances (one per CPU core, $ZRAM_MAX_DEVICES are the max)
@@ -45,7 +46,7 @@ activate_zram_swap() {
 		mkswap /dev/zram${i}
 		swapon -p 5 /dev/zram${i}
 	done
-	echo -e "### Activated ${zram_devices} zram swap devices with $(( ${mem_per_zram_device} / 1048576 )) MB each\n" >>${Log}
+	echo -e "\n### Activated ${zram_devices} zram swap devices with $(( ${mem_per_zram_device} / 1048576 )) MB each\n" >>${Log}
 } # activate_zram_swap
 
 activate_ramlog_partition() {
@@ -58,10 +59,16 @@ activate_ramlog_partition() {
 	ramlogsize=$(awk -F"=" '/^SIZE/ {print $2}' /etc/default/armbian-ramlog)
 	disksize=$(sed -e 's/M$/*1048576/' -e 's/K$/*1024/' <<<${ramlogsize:=50M} | bc)
 
-	# Try to choose most efficient compression scheme available -- https://patchwork.kernel.org/patch/9918897/
-	for algo in lz4 quicklz zlib brotli zstd ; do
-		echo ${algo} >/sys/block/zram0/comp_algorithm 2>/dev/null
-	done
+	# choose RAMLOG_ALGORITHM if defined in /etc/default/armbian-zram-config
+	# otherwise try to choose most efficient compression scheme available.
+	# See https://patchwork.kernel.org/patch/9918897/
+	if [ -n ${RAMLOG_ALGORITHM} ]; then		
+		echo ${RAMLOG_ALGORITHM} >/sys/block/zram0/comp_algorithm 2>/dev/null
+	else
+		for algo in lz4 lz4hc quicklz zlib brotli zstd ; do
+			echo ${algo} >/sys/block/zram0/comp_algorithm 2>/dev/null
+		done
+	fi
 	echo -n ${disksize} > /sys/block/zram0/disksize
 
 	# if it fails, select $swap_algo. Workaround for some older kernels
@@ -72,7 +79,7 @@ activate_ramlog_partition() {
 
 	mkfs.ext4 -O ^has_journal -s 1024 -L log2ram /dev/zram0
 	algo=$(sed 's/.*\[\([^]]*\)\].*/\1/g' </sys/block/zram0/comp_algorithm)
-	echo -e "### Activated Armbian ramlog partition with ${algo} compression\n" >>${Log}
+	echo -e "### Activated Armbian ramlog partition with ${algo} compression" >>${Log}
 } # activate_ramlog_partition
 
 case $1 in