It’s still possible that something is gradually getting bigger.
This is one of my tactics to see what’s going on:
# ps aux|sort -n +5|tail
systemd+ 1659 0.0 1.3 904384 54588 ? S 16:44 0:00 /usr/lib/postgresql/13/bin/postmaster -D /etc/postgresql/13/main
root 830 0.0 1.6 2253324 65208 ? Ssl 16:44 0:01 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
systemd+ 1682 0.0 1.9 904516 78092 ? Ss 16:44 0:01 postgres: 13/main: checkpointer
systemd+ 18757 0.1 2.1 912368 85644 ? Ss 18:06 0:00 postgres: 13/main: discourse discourse [local] idle
1000 1688 0.1 6.5 1006548 256428 ? Sl 16:44 0:10 unicorn master -E production -c config/unicorn.conf.rb
1000 2189 0.1 8.5 5657760 333248 ? Sl 16:45 0:06 unicorn worker[3] -E production -c config/unicorn.conf.rb
1000 2113 0.1 8.5 5656608 334352 ? Sl 16:45 0:07 unicorn worker[2] -E production -c config/unicorn.conf.rb
1000 2044 0.4 8.7 6052196 342380 ? Sl 16:44 0:23 unicorn worker[1] -E production -c config/unicorn.conf.rb
1000 2006 1.7 9.0 5628640 352492 ? Sl 16:44 1:33 unicorn worker[0] -E production -c config/unicorn.conf.rb
1000 1971 3.1 11.1 6033652 435388 ? SNl 16:44 2:54 sidekiq 6.5.12 discourse [0 of 5 busy]
(or ps auxc)