Ok, so I have some code to crawl a posting of a community and compare two servers for comments missing. It looks bad today. Both of these servers are version 0.18.0 and have been upgraded for several days.
missing 0 unequal 0 11 on https://lemmy.ml/ vs. 11 on https://sh.itjust.works/
missing 35 unequal 1 48 on https://lemmy.ml/ vs. 14 on https://sh.itjust.works/
missing 4 unequal 0 9 on https://lemmy.ml/ vs. 5 on https://sh.itjust.works/
missing 6 unequal 0 9 on https://lemmy.ml/ vs. 3 on https://sh.itjust.works/
missing 1 unequal 0 1 on https://lemmy.ml/ vs. 0 on https://sh.itjust.works/
missing 6 unequal 0 12 on https://lemmy.ml/ vs. 6 on https://sh.itjust.works/
missing 3 unequal 0 8 on https://lemmy.ml/ vs. 5 on https://sh.itjust.works/
missing 3 unequal 0 6 on https://lemmy.ml/ vs. 4 on https://sh.itjust.works/
missing 22 unequal 0 42 on https://lemmy.ml/ vs. 20 on https://sh.itjust.works/
missing 5 unequal 0 15 on https://lemmy.ml/ vs. 10 on https://sh.itjust.works/
missing 8 unequal 2 17 on https://lemmy.ml/ vs. 9 on https://sh.itjust.works/
missing 3 unequal 0 3 on https://lemmy.ml/ vs. 0 on https://sh.itjust.works/
missing 0 unequal 0 10 on https://lemmy.ml/ vs. 10 on https://sh.itjust.works/
missing 11 unequal 0 24 on https://lemmy.ml/ vs. 13 on https://sh.itjust.works/
missing 1 unequal 0 2 on https://lemmy.ml/ vs. 1 on https://sh.itjust.works/
missing 13 unequal 0 37 on https://lemmy.ml/ vs. 24 on https://sh.itjust.works/
missing 3 unequal 0 7 on https://lemmy.ml/ vs. 4 on https://sh.itjust.works/
missing 0 unequal 0 10 on https://lemmy.ml/ vs. 10 on https://sh.itjust.works/
missing 60 unequal 2 186 on https://lemmy.ml/ vs. 126 on https://sh.itjust.works/
missing 10 unequal 2 51 on https://lemmy.ml/ vs. 41 on https://sh.itjust.works/
missing 16 unequal 0 51 on https://lemmy.ml/ vs. 36 on https://sh.itjust.works/
missing 31 unequal 3 128 on https://lemmy.ml/ vs. 97 on https://sh.itjust.works/
missing 0 unequal 0 4 on https://lemmy.ml/ vs. 4 on https://sh.itjust.works/
missing 2 unequal 0 5 on https://lemmy.ml/ vs. 3 on https://sh.itjust.works/
missing 15 unequal 1 67 on https://lemmy.ml/ vs. 52 on https://sh.itjust.works/
missing 4 unequal 0 53 on https://lemmy.ml/ vs. 49 on https://sh.itjust.works/
missing 0 unequal 0 5 on https://lemmy.ml/ vs. 5 on https://sh.itjust.works/
missing 0 unequal 0 0 on https://lemmy.ml/ vs. 0 on https://sh.itjust.works/
missing 1 unequal 0 19 on https://lemmy.ml/ vs. 18 on https://sh.itjust.works/
missing 0 unequal 0 2 on https://lemmy.ml/ vs. 2 on https://sh.itjust.works/
missing 0 unequal 0 22 on https://lemmy.ml/ vs. 22 on https://sh.itjust.works/
missing 0 unequal 0 16 on https://lemmy.ml/ vs. 18 on https://sh.itjust.works/
missing 0 unequal 0 7 on https://lemmy.ml/ vs. 7 on https://sh.itjust.works/
missing 3 unequal 0 27 on https://lemmy.ml/ vs. 24 on https://sh.itjust.works/
missing 2 unequal 0 32 on https://lemmy.ml/ vs. 30 on https://sh.itjust.works/
missing 3 unequal 0 21 on https://lemmy.ml/ vs. 18 on https://sh.itjust.works/
missing 3 unequal 1 16 on https://lemmy.ml/ vs. 13 on https://sh.itjust.works/
missing 3 unequal 1 47 on https://lemmy.ml/ vs. 44 on https://sh.itjust.works/
missing 1 unequal 0 24 on https://lemmy.ml/ vs. 23 on https://sh.itjust.works/
The number of comments is based on loading comments, not the counts at the top of the posting.
The failures have more to do with server performance related to the quantity of new comments and activities than anything. There are periods of time that it fails worse than others and even when web browsers visiting the servers show errors.