That's a mystery to us. It was bumping up to the limit of php threads before, but that was not causing any problems. We don't know if the problem is because we updated PHP to 7.2 or if there was something else. In any case, removing the table optimization eliminated the outages for our users during those moments.
Re: Slowest queries are inserting single row into mdl_sessions
by Diane Soini -
Number of replies: 3
In reply to Diane Soini
Re: Slowest queries are inserting single row into mdl_sessions
by Jerry Lau -
Was it tested before? Changes would affect things.. change control for production? Replicate it test/development platform?
In reply to Jerry Lau
Re: Slowest queries are inserting single row into mdl_sessions
by Diane Soini -
We don't have an adequate simulation for our actual usage level. I was unable to create a viable simulation using Jmeter. We are a school of 20,000 undergraduates and for our upgrade from 3.1 to 3.5 we had only one developer.
In reply to Diane Soini
Re: Slowest queries are inserting single row into mdl_sessions
by Jerry Lau -
Yes.. sounds familiar