There was a bug in Lemmy where servers with large numbers of subscribers did a SQL query that overloaded the servers. Lemmy.ml and Lemmy.world were heavily impacted, given how many new instances have been added with people who subscribe to those big server communities!
From Lemmy.world:
I have been spot checking the comment replication on recent postings and messages are flowing far better.
Ah so that’s why it ran like shit. Good to know it’s back to normal!
Lemmy.ml vs. Lemmy.world on !asklemmy@lemmy.ml
Yes! So far, it’s working great today.
I can even upvote things without a json error!
Comparison of Lemmy.ml vs. Lemmy.world comments on !memes@lemmy.ml
node lemmyhelper_commandline.js posts --server0=https://lemmy.ml/ --server1=https://lemmy.ca/ --communityname asklemmy@lemmy.ml
Cheer
node lemmyhelper_commandline.js posts --server0=https://lemmy.ml/ --server1=https://lemm.ee/ --communityname asklemmy@lemmy.ml