My use is VPN and home router.
On a 64MB device running openvpn RAM never seems to fill up for me.
I see devices with GB’s of RAM?
What is RAM good for under openwrt VPN router use?
Wifi drivers have diff RAM requirements.
Qualcomm AX needs at least 512MB, while MediaTek AX is fine with 256MB.
If you don't use wifi, you might need less.
Especially newer wifi drivers (like ath10k and ath11k from Qualcomm) can be memory-hungry. The transmit speeds are so large that you also need large receive/send buffers etc.
My Raspberry Pi 4 router/server/samba has 4 gigs of ram and I notice sometimes the ram is nearly fully used up by by the "cache" as shown on the status page. I believe it caches content from my samba shares. Presumably for faster access to frequent files? If I reboot so the cache is empty, I can watch it grow at the same speed as my samba file transfers.
So my understanding, wired openvpn client only and no wifi, no real need for much RAM?
no, but openwrt itself is growing too (kernel and packages), even if you're able to run it on a 64MB RAM device today, there's no guarantee you'll be able to do it on next release, or the one after.
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