START=15
-ram_size()
+extra_command "compact" "Trigger compaction for all Z-RAM swap dev's"
+extra_command "status" "Print out information & statistics about Z-RAM swap devices"
+
+ram_getsize()
{
local line
while read line; do case "$line" in MemTotal:*) set $line; echo "$2"; break ;; esac; done </proc/meminfo
}
-zram_size() # in megabytes
+zram_getsize() # in megabytes
{
local zram_size="$( uci -q get system.@system[0].zram_size_mb )"
- local ram_size="$( ram_size )"
+ local ram_size="$( ram_getsize )"
if [ -z "$zram_size" ]; then
# e.g. 6mb for 16mb-routers or 61mb for 128mb-routers
- echo $(( $ram_size / 2048 ))
+ echo $(( ram_size / 2048 ))
else
echo "$zram_size"
fi
{
local zram_dev="$1"
- grep -sq ^"$zram_dev " /proc/swaps && {
- logger -s -t zram_applicable -p daemon.notice "[OK] '$zram_dev' already active"
- return 1
- }
-
[ -e "$zram_dev" ] || {
logger -s -t zram_applicable -p daemon.crit "[ERROR] device '$zram_dev' not found"
return 1
}
- which mkswap >/dev/null || {
- logger -s -t zram_applicable -p daemon.err "[ERROR] 'mkswap' not installed"
+ [ -x /sbin/mkswap ] || {
+ logger -s -t zram_applicable -p daemon.err "[ERROR] 'BusyBox mkswap' not installed"
return 1
}
- which swapon >/dev/null || {
- logger -s -t zram_applicable -p daemon.err "[ERROR] 'swapon' not installed"
+ [ -x /sbin/swapon ] || {
+ logger -s -t zram_applicable -p daemon.err "[ERROR] 'BusyBox swapon' not installed"
return 1
}
- which swapoff >/dev/null || {
- logger -s -t zram_applicable -p daemon.err "[ERROR] 'swapoff' not installed"
+ [ -x /sbin/swapoff ] || {
+ logger -s -t zram_applicable -p daemon.err "[ERROR] 'BusyBox swapoff' not installed"
return 1
}
}
zram_dev()
{
- local core="$1"
-
- echo "/dev/zram${core:-0}"
+ local idx="$1"
+ echo "/dev/zram${idx:-0}"
}
zram_reset()
echo "1" >"$proc_entry"
}
-list_cpu_idx()
+zram_getdev()
{
- # Offset by 1 if /dev/zram0 is in use by /tmp
- if [ "$(mount | grep /dev/zram0)" ]; then
- local line i=1
- # Hot-add new ZRAM device (if necessary)
- if [ ! -b /dev/zram1 ]; then
- cat /sys/class/zram-control/hot_add
- fi
+ #get unallocated zram dev
+ local zdev=$( zram_dev )
+
+ if [ "$(mount | grep $zdev)" ]; then
+ local idx=$(cat /sys/class/zram-control/hot_add)
+ zdev="$( zram_dev $idx )"
+ fi
+
+ echo $zdev
+}
+
+zram_comp_algo()
+{
+ local dev="$1"
+ local zram_comp_algo="$( uci -q get system.@system[0].zram_comp_algo )"
+
+ if [ -z "$zram_comp_algo" ]; then
+ # lzo-rle fails on small RAM devices, default to lzo, which is always available
+ zram_comp_algo="lzo"
+ fi
+
+ if [ $(grep -c "$zram_comp_algo" /sys/block/$( basename $dev )/comp_algorithm) -ne 0 ]; then
+ logger -s -t zram_comp_algo -p daemon.debug "Set compression algorithm '$zram_comp_algo' for zram '$dev'"
+ echo $zram_comp_algo > "/sys/block/$( basename $dev )/comp_algorithm"
else
- local line i=0
+ logger -s -t zram_comp_algo -p daemon.debug "Compression algorithm '$zram_comp_algo' is not supported for '$dev'"
fi
-
- while read line; do {
- case "$line" in
- [Pp]rocessor*)
- echo $i
- i=$(( $i + 1 ))
- ;;
- esac
- } done <"/proc/cpuinfo"
}
-start()
+zram_comp_streams()
+{
+ local dev="$1"
+ local logical_cpus=$( grep -ci "^processor" /proc/cpuinfo )
+ [ $logical_cpus -gt 1 ] || return 1
+ local zram_comp_streams="$( uci -q get system.@system[0].zram_comp_streams )"
+ [ -n "$zram_comp_streams" ] && [ "$zram_comp_streams" -le "$logical_cpus" ] || zram_comp_streams=$logical_cpus
+ if [ -e /sys/block/$( basename $dev )/max_comp_streams ]; then
+ logger -s -t zram_comp_streams -p daemon.debug "Set max compression streams to '$zram_comp_streams' for zram '$dev'"
+ echo $zram_comp_streams > /sys/block/$( basename $dev )/max_comp_streams
+ fi
+}
+
+#print various stats info about zram swap device
+zram_stats()
+{
+ local zdev="/sys/block/$( basename "$1" )"
+
+ printf "\nGathering stats info for zram device \"$( basename "$1" )\"\n\n"
+
+ printf "Z-RAM\n-----\n"
+ printf "%-25s - %s\n" "Block device" $zdev
+ awk '{ printf "%-25s - %d MiB\n", "Device size", $1/1024/1024 }' <$zdev/disksize
+ printf "%-25s - %s\n" "Compression algo" "$(cat $zdev/comp_algorithm)"
+ printf "%-25s - %s\n" "Compression streams" "$( cat $zdev/max_comp_streams)"
+
+ awk 'BEGIN { fmt = "%-25s - %.2f %s\n"
+ fmt2 = "%-25s - %d\n"
+ print "\nDATA\n----" }
+ { printf fmt, "Original data size", $1/1024/1024, "MiB"
+ printf fmt, "Compressed data size", $2/1024/1024, "MiB"
+ printf fmt, "Compress ratio", $1/$2, ""
+ print "\nMEMORY\n------"
+ printf fmt, "Memory used, total", $3/1024/1024, "MiB"
+ printf fmt, "Allocator overhead", ($3-$2)/1024/1024, "MiB"
+ printf fmt, "Allocator efficiency", $2/$3*100, "%"
+ printf fmt, "Maximum memory ever used", $5/1024/1024, "MiB"
+ printf fmt, "Memory limit", $4/1024/1024, "MiB"
+ print "\nPAGES\n-----"
+ printf fmt2, "Same pages count", $6
+ printf fmt2, "Pages compacted", $7 }' <$zdev/mm_stat
+
+ awk '{ printf "%-25s - %d\n", "Free pages discarded", $4 }' <$zdev/io_stat
+}
+
+zram_compact()
{
- # http://shmilyxbq-compcache.googlecode.com/hg/README
- # if >1 cpu_core, reinit kmodule with e.g. num_devices=4
+ # compact zram device (reduce memory allocation overhead)
+ local zdev="/sys/block/$( basename "$1" )"
- local zram_size="$( zram_size )"
- local zram_dev core
+ local old_mem_used=$(awk '{print $3}' <$zdev/mm_stat)
+ local old_overhead=$(awk '{print $3-$2}' <$zdev/mm_stat)
- for core in $( list_cpu_idx ); do {
- zram_dev="$( zram_dev "$core" )"
- zram_applicable "$zram_dev" || return 1
+ echo 1 > $zdev/compact
- logger -s -t zram_start -p daemon.debug "activating '$zram_dev' for swapping ($zram_size MegaBytes)"
+ # If not running interactively, than just return
+ [ -z "$PS1" ] && return 0
- zram_reset "$zram_dev" "enforcing defaults"
- echo $(( $zram_size * 1024 * 1024 )) >"/sys/block/$( basename $zram_dev )/disksize"
- mkswap "$zram_dev"
- swapon "$zram_dev"
- } done
+ echo ""
+ echo "Compacting zram device $zdev"
+ awk -v old_mem="$old_mem_used" -v ovr="$old_overhead" 'BEGIN { fmt = "%-25s - %.1f %s\n" }
+ { printf fmt, "Memory usage reduced by ", (old_mem-$3)/1024/1024, "MiB"
+ printf fmt, "Overhead reduced by", (ovr-($3-$2))/ovr*100, "%" }' <$zdev/mm_stat
}
-stop()
+start()
{
- local zram_dev proc_entry
+ if [ $( grep -cs zram /proc/swaps ) -ne 0 ]; then
+ logger -s -t zram_start -p daemon.notice "[OK] zram swap is already mounted"
+ return 1
+ fi
- for core in $( list_cpu_idx ); do {
- zram_dev="$( zram_dev "$core" )"
- proc_entry="/sys/block/$( basename "$zram_dev" )/reset"
+ local zram_size="$( zram_getsize )"
+ local zram_dev="$( zram_getdev )"
+ zram_applicable "$zram_dev" || return 1
+ local zram_priority="$( uci -q get system.@system[0].zram_priority )"
+ zram_priority=${zram_priority:+-p $zram_priority}
- grep -sq ^"$zram_dev " /proc/swaps && {
- logger -s -t zram_stop -p daemon.debug "deactivate swap $zram_dev"
- swapoff "$zram_dev"
- }
+ logger -s -t zram_start -p daemon.debug "activating '$zram_dev' for swapping ($zram_size MegaBytes)"
+
+ zram_reset "$zram_dev" "enforcing defaults"
+ zram_comp_algo "$zram_dev"
+ zram_comp_streams "$zram_dev"
+ echo $(( $zram_size * 1024 * 1024 )) >"/sys/block/$( basename "$zram_dev" )/disksize"
+ /sbin/mkswap "$zram_dev"
+ /sbin/swapon -d $zram_priority "$zram_dev"
+}
- zram_reset "$zram_dev" "claiming memory back"
+stop()
+{
+ local zram_dev
+
+ for zram_dev in $( grep zram /proc/swaps |awk '{print $1}' ); do {
+ logger -s -t zram_stop -p daemon.debug "deactivate swap $zram_dev"
+ /sbin/swapoff "$zram_dev" && zram_reset "$zram_dev" "claiming memory back"
+ local dev_index="$( echo $zram_dev | grep -o "[0-9]*$" )"
+ if [ $dev_index -ne 0 ]; then
+ logger -s -t zram_stop -p daemon.debug "removing zram $zram_dev"
+ echo $dev_index > /sys/class/zram-control/hot_remove
+ fi
+ } done
+}
+
+# show memory stats for all zram swaps
+status()
+{
+ for zram_dev in $( grep zram /proc/swaps |awk '{print $1}' ); do {
+ zram_stats "$zram_dev"
} done
}
+# trigger compaction for all zram swaps
+compact()
+{
+ for zram_dev in $( grep zram /proc/swaps |awk '{print $1}' ); do {
+ zram_compact "$zram_dev"
+ } done
+}
projects / openwrt / staging / jow.git / blobdiff