Hi,
Why do things slow down after a lot of updates without a VACUUM? This
slow-down doesn't seem to happen as much with a lot of inserts.
Don't the indexes know which is the valid updated row? Or does Postgresql
still have to search for it amongst deleted/invalid rows?
I can understand why the database would bloat up and/or slow down slightly
without a vacuum. But why such a significant slowdown? So much so that
people have to vacuum every two hours.
Cheerio,
Link.