Nothing spectacular, but I wanted to share that even devices low on RAM (32MB) still work for simple tasks.
In this case there were a few TP-Link 1043nd v1 I had lying around (https://openwrt.org/toh/tp-link/tl-wr1043nd) with only 32MB of RAM.
In my setup one was configured to operate as WDS-client, bridged to LAN ports for a server that has no WiFi.
Since RAM is scarce it makes sense to remove unneeded things:
#!/bin/bash
BUILDER="https://downloads.openwrt.org/releases/21.02.3/targets/ath79/generic/openwrt-imagebuilder-21.02.3-ath79-generic.Linux-x86_64.tar.xz"
# download image builder
if [ ! -f "${BUILDER##*/}" ]; then
wget "$BUILDER"
tar xJvf "${BUILDER##*/}"
fi
cd openwrt-*/
# list all targets for this image builder, consider 'make help' as well
#make info
# clean previous images
make clean
# Packages are added if no prefix is given, '-packagename' does not integrate/removes a package
make image PROFILE="tplink_tl-wr1043nd-v1" \
PACKAGES="-firewall -kmod-ip6tables -kmod-ipt-conntrack \
-kmod-ipt-core -kmod-ipt-nat -kmod-ipt-offload kmod-mac80211 kmod-nf-conntrack -kmod-nf-conntrack6 -kmod-nf-flow -kmod-nf-ipt \
-kmod-nf-ipt6 -kmod-nf-nat -kmod-nf-reject -kmod-nf-reject6 -kmod-ppp -kmod-pppoe -kmod-pppox -ppp -luci-proto-ppp -luci-proto-ipv6 -luci-app-firewall \
-ppp -ppp-mod-pppoe \
-ip6tables -odhcp6c -kmod-ipv6 -kmod-ip6tables -odhcpd-ipv6only \
-odhcpd \
-iptables \
-opkg \
zram-swap \
uhttpd uhttpd-mod-ubus libiwinfo-lua luci-base luci-mod-admin-full luci-theme-bootstrap \
-wpad-basic-wolfssl wpad-wolfssl \
luci-app-statistics collectd-mod-ping collectd-mod-wireless collectd-mod-uptime \
pingcheck htop"
exit 0
To test the setup the server ran an iperf3 session for a day:
while true; do iperf3 -c 192.168.1.123 -t90; sleep 1; iperf3 -c 192.168.1.123 -R -t90; sleep 1; done
And the device managed to handle that quite Ok (I stopped at ~21:00):
TL;DR: Don't expect wonders, such hardware is still old. Even devices with 32MB can be used for simple tasks. Use SystemBuilder to free/compress RAM. No need to throw the hardware away yet.
Edit:
After configuring/diagnosing/testing it makes sense to disable uhttpd and collectd to free RAM and mitigate OOM issues. Enter console and issue the commands:
/etc/init.d/collectd stop
/etc/init.d/luci_statistics stop
/etc/init.d/uhttpd stop
/etc/init.d/collectd disable
/etc/init.d/luci_statistics disable
/etc/init.d/uhttpd disable
If you like to have LuCI running temporarily, just start it from the console with /etc/init.d/uhttpd start
