Full Ram asus rt-58u openwrt

Dear all,
I already build and flash successful Openwrt to AP asus rt-58u. It work fine for 3-4 devices, but it is suddenly full ram. Sometime I can't load Luci web browser, it work normal when I reboot AP and fine only 10 minutes and get full ram again. Anyone have same issue with me, please share solution. Thanks so much

root@OpenWrt:~# free
              total        used        free      shared  buff/cache   available
Mem:         121020       90352       25164         112        5504        4376
Swap:             0           0           0

There is no fix, 802.11ac in general and ath10k in particular are a relatively memory hungry, for a device with two ath10k radios, 128 MB RAM are tight, borderline too tight.

While there is no fix, there are mitigating workarounds to reduce the size- and number of buffers allocated by the kernel module. For the 18.06.x branch and ath10k, those should already be applied by default, for the master branch -which switched to ath10k-ct instead of ath10k- the equivalent patches are still pending. If you're building OpenWrt/ master from source, you can apply these patches to your build (depending on the used ath10k-ct version, you may have to rebase these patches in the future).

If you're looking to buy additional hardware, please do yourself a favour and prefer devices (at least for dual-ath10k based ones) with at least 256 MB RAM instead (most other ipq40xx devices ship with 256 MB RAM or more for good reasons).

I have this device too and I have to use a swap partition on a USB drive. No problem so far though I installed Adblock, Transmission and Unbound

Dear @utopinux
How do you set up for your asus rt-58u. Could you share your configuration. I research this link for install package

but my AP always full out memory, I can't do anything. It just work fine 5 minutes after reboot.

Use of internal flash is not recommended for swap as it will wear it out very quickly and eventually kill your router. The better USB sticks have transfer rates around 5-10 MB/s, common ones more like 1-2 MB/s -- Do the math with 128 MB of RAM and realize that this may bring your router to a crawl.

1 Like

I think you can start with this.
You must have a spare USB ( 512MB is fine) around which can be formated as a swap drive. You can use Minitool Partition Wizard ( if you use Windows) or any similar software to do it . Then you can use Luci web interface to config it as a swap.
Unless you already installs alot of services and lot of clients, the router works fine with 128MB of RAM.
I config my router with 1 TB hard drive including two partitions (swap + ext4). I'm running Adblock, Samba, Tranmission, SQM, DDNS, wireguard, shadowsocks, openvpn , unbound, wifi-schedule, hd-iddle... and the swap is stable at around 40MB.
Hope it helps!