Looks like it works.

Edit still see some performance issues. Needs more troubleshooting

Update: Registrations re-opened We encountered a bug where people could not log in, see https://github.com/LemmyNet/lemmy/issues/3422#issuecomment-1616112264 . As a workaround we opened registrations.

Thanks

First of all, I would like to thank the Lemmy.world team and the 2 admins of other servers @stanford@discuss.as200950.com and @sunaurus@lemm.ee for their help! We did some thorough troubleshooting to get this working!

The upgrade

The upgrade itself isn’t too hard. Create a backup, and then change the image names in the docker-compose.yml and restart.

But, like the first 2 tries, after a few minutes the site started getting slow until it stopped responding. Then the troubleshooting started.

The solutions

What I had noticed previously, is that the lemmy container could reach around 1500% CPU usage, above that the site got slow. Which is weird, because the server has 64 threads, so 6400% should be the max. So we tried what @sunaurus@lemm.ee had suggested before: we created extra lemmy containers to spread the load. (And extra lemmy-ui containers). And used nginx to load balance between them.

Et voilà. That seems to work.

Also, as suggested by him, we start the lemmy containers with the scheduler disabled, and have 1 extra lemmy running with the scheduler enabled, unused for other stuff.

There will be room for improvement, and probably new bugs, but we’re very happy lemmy.world is now at 0.18.1-rc. This fixes a lot of bugs.

  • Zetaphor@zemmy.ccEnglish
    6·
    1 year ago

    There is a lot of work being put into optimizing the Lemmy backend. There is a LOT of low hanging fruit in regards to performance gains from database bottlenecks.

    Lemmy was an obscure platform with only ~1k total active users last month, it’s going to take time for the maintainers to get their bearings, the developer community to organize, and for everyone to figure out how to maintain and scale these operations at the number of users we’re seeing today and going forward.

    The upgrade to 0.18.1 alone brings with it major performance improvements and there is more to come. We can get a lot more mileage out of the hardware we’re using today, it’s just that the platform blew up in scale before the all of the can bottlenecks were identified and worked out.