diff --git a/lib.sh b/lib.sh
index e9f1275..a4a6658 100644
--- a/lib.sh
+++ b/lib.sh
@@ -28,14 +28,6 @@ download_isos() {
     "${curl[@]}"
 }
 
-_getmaxram() {
-    local ram; ram="$(free -g | awk '/^Mem:/{print $2 - 2}')"
-
-    if   [ "$ram" -le  2 ]; then  ram=2
-    elif [ "$ram" -gt 32 ]; then ram=32; fi
-    echo "${ram}G"
-}
-
 _getnet() {
     local net=user
 
@@ -49,18 +41,18 @@ _getnet() {
 }
 
 qemu() {
-    local ram=2G
-    local maxram; maxram="$(_getmaxram)"
-    local net; net="$(_getnet)"
+    local ram net
 
+    ram="$(free -g | awk '/^Mem:/{t=$2 / 2; print(t < 2 ? 2 : t)"G"}')"
+    net="$(_getnet)"
     (set -x
     qemu-system-x86_64 \
         -accel   kvm \
         -M       q35 \
         -bios    /usr/share/edk2/x64/OVMF.4m.fd \
         -monitor stdio \
-        -cpu     host \
-        -m       "$ram,maxmem=$maxram" \
+        -smp     "$(nproc --ignore 4)" \
+        -m       "$ram" \
         -vga     virtio \
         -audio   pipewire,model=hda \
         -nic     "model=virtio-net-pci,type=$net" \
diff --git a/startnat.sh b/startnat.sh
index c8171d6..7c342df 100755
--- a/startnat.sh
+++ b/startnat.sh
@@ -1,15 +1,14 @@
 #!/bin/bash -eu
-DIR="$(dirname "${BASH_SOURCE[0]}")"
 
 fix_nft_drops() {
     local j s='"add chain \(.family) \(.table) \(.name) { policy \(.policy); }"'
 
-    if [ -f "$DIR/restore-nft.conf" ]; then
-        nft -f "$DIR/restore-nft.conf"
+    if [ -f /tmp/restore-nft.conf ]; then
+        nft -f /tmp/restore-nft.conf
     fi
     j="$(nft -j list chains | jq '.[][].chain | select(.policy == "drop")')"
     jq -r ".policy=\"accept\" | $s" <<< "$j"
-    jq -r "$s" <<< "$j" > "$DIR/restore-nft.conf"
+    jq -r "$s" <<< "$j" > /tmp/restore-nft.conf
 }
 
 command -V dnsmasq > /dev/null
@@ -29,7 +28,6 @@ if ! ip link show "$BRIDGE" 2> /dev/null; then
     ip link add "$BRIDGE" type bridge
 fi
 ip link set dev "$BRIDGE" up
-ip address flush dev "$BRIDGE"
 ip address add 192.168.123.1/24 dev "$BRIDGE"
 
 nft -f- <<EOF
@@ -50,7 +48,7 @@ destroy table ip qemu; table ip qemu {
 }
 EOF
 
-if ! pidof dnsmasq | grep -q "$(cat /var/run/dnsmasq-virbr0.pid)"; then
+if ! [ -f /var/run/dnsmasq-virbr0.pid ]; then
     dnsmasq -z \
         -i "$BRIDGE" \
         -F 192.168.123.2,192.168.123.254,255.255.255.0 \
diff --git a/stopnat.sh b/stopnat.sh
index a5c59e6..0ecbf31 100755
--- a/stopnat.sh
+++ b/stopnat.sh
@@ -5,14 +5,13 @@ if [ "$EUID" != 0 ]; then
     exit
 fi
 
-BRIDGE="${1-virbr0}"
-
-ip link del dev "$BRIDGE"
+ip link del dev "${1-virbr0}"
 
 nft destroy table qemu
-if [ -f restore-nft.conf ]; then
-    nft -f ./restore-nft.conf
-    rm restore-nft.conf
+if [ -f /tmp/restore-nft.conf ]; then
+    nft -f /tmp/restore-nft.conf
+    rm /tmp/restore-nft.conf
 fi
 
-kill -TERM "$(cat /var/run/dnsmasq-virbr0.pid)"
+kill -TERM "$(< /var/run/dnsmasq-virbr0.pid)"
+rm -f /var/run/dnsmasq-virbr0.pid