Feature request: reduce memory usage

[qdm12]

What's the feature 🧐

I noticed memory usage goes to 300MB / 500MB even when using the kernel space Wireguard implementation and this is simply ridiculous (self shaming).

A pprof HTTP server should be setup to investigate why memory is so high.

Wild guesses are:

• Server data being loaded in memory and always kept. This can be changed to be lazy loaded from files.

Extra information and references

No response

[alpe12]

Just noticed I have 461MB usage with nordvpn openvpn here.
Going back to edgd1er/nordvpn-proxy for the time being. Only 19MB ram usage there.

[qdm12]

After investigation, ram usage splits in the following:

• Unbound: 283MB
• Gluetun program: 35MB
  • Blacklist builder Hostnames uses 30MB (this will be addressed)
  • DNS Blacklist's getList uses 15MB (this will be addressed)
  • Built-in servers data uses 2.5MB so it is clearly not a priority (this has been worked on)
  • Rest of the program uses barely anything

Turning BLOCK_MALCIOUS=off brings down the container memory usage to about 50MB. I won't change this by default to not break compatibility.

#137 is coming soon and might improve the memory usage, although blocking hostnames/IPs at the DNS level will always incur more memory usage.

Closing this as there is not so much possible to do, except turning off DNS blocking.

[qdm12]

Any option to have the blacklist, etc on disk and only active queries are cached into memory? If not maybe con1sider adding an option for a external (local container) DNS server option to off load this? E.g If someone is running 2 Gluetun tunnels only a single DNS server is required.

[amirnh2]

I've set the following environments:
- BLOCK_MALICIOUS=off
- BLOCK_SURVEILLANCE=off
- BLOCK_ADS=off
- DOT=off

htop shows a memory usage of about 24.5 MB for gluetun-entrypoint, and 4.2 MB for the openvpn2.5 process.

Is there any way to reduce the entry-point ram usage? or is this the lowest gluetun can go? Because I need to run many gluetun containers and I need them to consume the lowest ram possible.

[qdm12]

I'll have a look. I know ~3MB are used to have all the server data in memory at runtime, and that can be moved to lazy loading from disk. But apart from that, there might not be a way to reduce it further as I remember.

[amirnh2]

I hope there's a way.

Thank you for this great repository.

[qdm12]

You can dig into it by profiling the heap following steps in this new wiki page: https://github.com/qdm12/gluetun/wiki/Profiling
Maybe you can spot a place where most MBs of memory go. Although the Go runtime probably use ~10MB anyway, so it might not be very possible to lower memory usage that much.