[Done] Lemmy world was upgraded to 0.18.3 today (2023-07-30)
Update
The upgrade was done, DB migrations took around 5 minutes. We'll keep an eye out for (new) issues but for now it seems to be OK.
Original message
We will upgrade lemmy.world to 0.18.3 today at 20:00 UTC+2 (Check what this isn in your timezone). Expect the site to be down for a few minutes. ""Edit"" I was warned it could be more than a few minutes. The database update might even take 30 minutes or longer.
This version brings major optimizations to the database queries, which significantly reduces CPU usage. There is also a change to the way federation activities are stored, which reduces database size by around 80%. Special thanks to @phiresky for their work on DB optimizations.
The federation code now includes a check for dead instances which is used when sending activities. This helps to reduce the amount of outgoing POST requests, and also reduce server load.
In terms of security, Lemmy now performs HTML sanitization on all messages which are submitted through the API or received via federation. Together with the tightened content-security-policy from 0.18.2, cross-site scripting attacks are now much more difficult.