Linksys MR7350 crash under heavy network load

Hello
I have an issue with my Linksys MR7350 (OpenWrt 25.12.4 r32933-4ccb782af7 / LuCI openwrt-25.12 branch 26.151.60189~17deb6e)

The router dies under heavy network load.

Setup:
15 Wifi Clients
10 LAN Clients

Everything is running stable until a HUGE download is started.
The router began to consume RAM, until he restarts.

Setup:
Windows PC connected via cable

Before..


Testing with 4 downloads

3 times with wget
wget --no-check-certificate https://ftp.halifax.rwth-aachen.de/opensuse/distribution/openSUSE-current/iso/Leap-16.0-offline-installer-aarch64.install.iso -O /dev/null

1 download via nzb
https://sabnzbd.org/tests/test_download_10GB.nzb

Result:


And then it's gone...

Any tips ?


ATM only the PS5 is downloading a game update :wink:

After reboot

All downloads finished...

looks like the memory hungry qualcom ran out of memory.

Try installing kmod-zram, and reboot, it will however come with a performance penalty.


Already install it

Not sure how it works, never had to use it myself, try to increase the zram size ?

Make sure you DL a backup of your config before you start to play with the settings.

i already tried to play around with the zram size.
I does not have any influcence...
The router is working stable without any problems...

except for the problems with the HUGE downloads :wink:

Well, "we" knew 512MB RAM on QCA was going to be tight :frowning:

Check sysctl params, see if you can reduce some of the connection timeout values, in hope it'll deallocate RAM quicker.
Reducing the amount of parallel connections in SAB might also help.

If you're not on 1gbit (and I guess you're not) using 50 connections in SAB is probably not required.
Try to tweak the connections, but still reach full speed from your news server provider(s).

On SAB i use 20 connections :wink:
I already disabled all IPV6 stuff... this helps a bit...

so... for now i have to live with it :wink:


After nearly 3 hours, memory usage is ok....

You could probably squeeze out some more, by disabling the DNS in dnsmasq and pointing all your clients to an upstream DNS, ISP's or public.