I took a quick look at the log files and I have identified a query that appears to be causing delays for other threads/requestors in the system and is likely the slowness that you are experiencing. I believe there are locks associated with that query. Once these queries finish, then the other processes/threads waiting for them complete. Since you are running Oracle, I would suggest working with your DBA to run an explain plan to see where the slowness is occurring and identify if any indexes/statistic updates are needed to make the query run faster. The attached document lists 3 instances of the query, one for Check-in, delete, and saveas. In addition, I did see some PEGA0017 alerts that may indicate a cache hit issue and provided a solution for that in the document as well.
I do not see the same query as being a problem in this latest alert log you provided. This looks more like slowness with searches. See Attached for examples. Can you confirm the activity that was being done when the slowness occurred?