When placing down lava, I noticed a short lag spike. Pulling up the fps debug thing, its very clear the lava bucket is causing fps spikes when used. Interestingly, this bug is not present when using a water bucket.
MC-219928
fps/lag spike when placing/filling lava bucket
Resolved
Cannot Reproduce
0
Having difficulty launching older snapshot to see if this was previously present in 21w10a. But I don't remember having mini-lag spikes the last time I played 21w10a. This issue might be a result of the fix for MC-12363