After a Redshift's Maintenance my queries are too slow

There are some possible explanations to the behavior you're observing. For example, it is possible that a Redshift software upgrade forces an invalidation of your cluster's global query compile cache if the compile logic was changed as part of the release, but this is just one theory and I would be surprised if this happens with every software upgrade. The best course of action that I can recommend is to open a support ticket, so the AWS/Redshift support team can diagnose your cluster with you in real time.

These maintenances were done early Saturday morning : REDSHIFT-EVENT-3014 REDSHIFT-EVENT-3520 REDSHIFT-EVENT-3519 REDSHIFT-EVENT-2004 REDSHIFT-EVENT-2003 On Saturday during the day I connected to my reports and all queries were very slow. This happens after every amazon maintenance. I haven't tried to contact account support yet, I wanted to find out if this behavior was encountered by other users.

Hello, to best answer your question, I think a few follow-up questions are needed. For example, you mention cluster maintenance (e.g. Redshift software upgrade), but am wondering if it is really automatic table maintenance that is being referred to (e.g. automatic sort key optimization). Also, is it all queries exhibiting a slow-down or just some queries? Have you tried reaching out to account support or your account solutions architect for help possibly examining your cluster with you in real time?