CPU and Memory Monitoring

Does anyone has setup to collect Database Server CPU and memory utilization from database when you are missing the access to the database server ?  I want to collect Oracle Memory and CPU utilization every 15min to 30 min and record in table for analysis.  I know OSwatcher can take care of it all but there is no access to this critical production environment where our company is on supporting application and want to make sure system resources as well as application utilization is good. We only have Database user to access using SQl or client tool but has permission to access any Database views. I saw one of the very good article for the same to measure CPU from C. Antognini at  Report Information about CPU Activity in SQL*Plus – Striving for Optimal Performance and it work very fine to get CPU details. as long as I had permission to create the objects but I had only access granted using Role  So if someone has other details to get the same for Memory and other direct query to run as plSQL script or sharing any more information. TIA
Sanjay

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