I tried to upgrade phpBB forum from 3.1.8 to 3.2.3, all by this instruction
using phpcli tool, process went with no error, users were happily using site for few hours. But I've found that row reads went from small numbers (like 1 million rows read per hour for 3.1.8) to bigger like 70-100 million row reads per hour. I switched back to old version (yup, good old backups), so no big problem for now, but I'd like to eventually upgrade forum version to new one. I can't let it run with so many reads, because it's shared hosting that allow for only limited number of reads per day which this 3.2.3 forum would "eat" in only few hours.
What can I do about it? I have no idea where to start searching for the problem.
I've turned off all extensions for few hours (and db row reads didn't come lower) so looks like it's not extension problem.
Before 3.1.8, this forum was run under 2.x "phpbb by Przemo" (Polish version; by previous admin), I converted it to 3.1.8 about two years ago, if that's something relevant.
Any help appreciated
if I'm to provide more information - just ask question. If there is someone willing to take a closer look, I have this 3.2.3 forum running "in shadow" and can provide admin account and so on. Unfortunately, as it's shared hosting, I don't have satisfactory access to logs.