Via @Danvil in #7222 (comment):

With branch master (as of 8/27, 3PM PDT) it feels a little bit faster but performance is still lower than rerun 0.16.

I tried some bisection of the rerun visualizations in my application and the bottleneck now seems to be this code:

rr.set_time_seconds("timestamp", my_timestamp);
rr.log("path", &rerun::Clear::recursive())?;
for (i, pose) in path.iter().enumerate() {
    rr.log(format!("{tag}/{i}"), &rerun::Transform3D::from_translation_mat3x3(pose.t3, pose.r3))?;
}

(there are 250 poses)

Without this visualization 0.18 also is much faster. So it seems like a large part of the slowdown from 0.16 to 0.18 is due to visualization of the poses.