diff --git a/README.md b/README.md
index 9b19134..ad1d5eb 100644
--- a/README.md
+++ b/README.md
@@ -7,5 +7,6 @@ Following settings are made:
 - Upgrade system to latest version
 - Install basic tools: `sudo vim ifupdown2 net-tools dnsutils ethtool git curl unzip screen iftop lshw smartmontools nvme-cli lsscsi sysstat zfs-auto-snapshot htop mc rpl`
 - Configure snapshot retention for `zfs-auto-snapshot` interactively
-- Calculates limits for level 1 arc (`zfs_arc_min` and `zfs_arc_max`) based on all configured zpools
+- `zfs_arc_[min|max]` will be calculated by size sum of all zpools in 512 MB steps
 - Configure backup of `/etc` folder to new zfs dataset on `rpool/pveconf`
+- configure `vm.swappiness` interactively
diff --git a/proxmox-zfs-postinstall.sh b/proxmox-zfs-postinstall.sh
index 6465b2c..54ca476 100644
--- a/proxmox-zfs-postinstall.sh
+++ b/proxmox-zfs-postinstall.sh
@@ -12,7 +12,7 @@ TOOLS="sudo vim ifupdown2 net-tools dnsutils ethtool git curl unzip screen iftop
 PVE_CONF_BACKUP_TARGET=rpool/pveconf
 
 # Define timer for your backup cronjob (default: every 15 minutes fron 3 through 59)
-PVE_CONF_BACKUP_CRON_TIMER="3/15 * * * *"
+PVE_CONF_BACKUP_CRON_TIMER="3,18,33,48 * * * *"
 
 
 ###### SYSTEM INFO AND INTERACTIVE CONFIGURATION SECTION ######
@@ -192,10 +192,10 @@ echo $ZFS_ARC_MAX_BYTES > /sys/module/zfs/parameters/zfs_arc_max
 
 cat << EOF > /etc/modprobe.d/zfs.conf
 options zfs zfs_arc_min=$ZFS_ARC_MIN_BYTES
-options zfs zfs_arc_min=$ZFS_ARC_MAX_BYTES
+options zfs zfs_arc_max=$ZFS_ARC_MAX_BYTES
 EOF
 
 echo "Updating initramfs - This will take some time..."
 update-initramfs -u -k all > /dev/null 2>&1
 
-echo "Proxmox postinstallation finished!"
\ No newline at end of file
+echo "Proxmox postinstallation finished!"