I spent several hours tracing in production (updating the code a dozen times with extra logging) to identify the actual path the lemmy_server code uses for outbound federation of votes to subscribed servers.
Major popular servers, Beehaw, Leemy.world, Lemmy.ml - have a large number of instance servers subscribing to their communities to get copies of every post/comment. Comment votes/likes are the most common activity, and it is proposed that during the PERFORMANCE CRISIS that outbound vote/like sharing be turned off by these overwhelmed servers.
pull request for draft:
EDIT: LEMMY_SKIP_FEDERATE_VOTES environment variable
I have no idea why the file is named “mod.rs”, as normal non-admin non-moderator users seem to go through this code path.
this is a rust thing: https://stackoverflow.com/questions/26435102/in-rust-what-is-the-purpose-of-a-mod-rs-file
ahh, ok. I’m sure I’ll keep getting confused because of content moderator in my mind. Thanks.
ok, I figured out how to get Rust to match the enum, is there a way to do this with match instead of if statements?
+ if let AnnouncableActivities::UndoVote(_) = activity { + warn!("zebratrace310 SKIP UndoVote"); + } else if let AnnouncableActivities::Vote(_) = activity { + warn!("zebratrace310A SKIP Vote"); + } else { + warn!("zebratrace311 send"); + AnnounceActivity::send(activity.clone().try_into()?, community, context).await?; + };
Code seems to work great, blocks UndoVote/Vote but does the send on comment reply.
more “correct” way would be this:
match activity { AnnouncableActivities::UndoVote(_) => warn!("zebratrace310 SKIP UndoVote"), AnnouncableActivities::Vote(_) => warn!("zebratrace310A SKIP Vote"), _ => { warn!("zebratrace311 send"); AnnounceActivity::send(activity.clone().try_into()?, community, context).await?; }, }
here it is in the rust book: https://doc.rust-lang.org/stable/book/ch06-02-match.html
ool. I found the syntax for multiple hits, so I was looking for:
match activity { AnnouncableActivities::UndoVote(_) | AnnouncableActivities::Vote(_) => { warn!("zebratrace310 SKIP federating Vote/UndoVote"); }, _ => { warn!("zebratrace311 send"); AnnounceActivity::send(activity.clone().try_into()?, community, context).await?; }, }
Thank you.