Federation likes (votes) are wildly different from server to server as it stands now. And unless something is way off on my particular server, 0.4 seconds is what PostgreSQL is reporting as the mean (average) time per single comment vote INSERT, and post vote INSERT is similar. (NOTE: my server is classic hard drives, 100MB/sec bencharked, not a SSD)
Discussion of the SQL statement for a single comment vote insert: https://lemmy.ml/post/1446775
Every single VOTE is both a HTTP transaction from the remote server and a SQL transaction. I am looking into Postgress supporting batches of inserts to not check all the index constraints at each single insert: https://www.postgresql.org/docs/current/sql-set-constraints.html
Can the Rust code for inserts from federation be reasonably modified to BEGIN TRANSACTION only every 10th comment_like INSERT and then do a COMMIT of all of them at one time? and possibly a timer that if say 15 seconds passes with no new like entries from remote servers, do a COMMIT to flush based a timeout.
Storage I/O writing for votes alone is pretty large…
I made a major mistake (discovered yesterday), it’s been over a decade since I ran a major Postgres website. The units were fractions of a millisecond, not seconds. So that was 10 milliseconds.
At this point I don’t have reason to hide the data, here is my two significant server stats:
https://lemmyadmin.bulletintree.com/query/pgcounts?output=table Record counts in tables https://lemmyadmin.bulletintree.com/query/pgstatements?output=table pg_stat_statement extension output, curated columns. Full columns is available if you need it: https://lemmyadmin.bulletintree.com/query/pgstatements1?output=table
Feel free to refresh these pages as much as you like. The pg_stat_statement can be reset, I think I reset them 24 hours ago.
Server is 4 ARM cores, 24 GB of RAM, 200GB IDE level storage performance (Oracle Cloud). There are no interactive users other than myself and perhaps some Google traffic. Federation is the main activity, and I’ve been subscribing to as many big communities as I can for weeks.