Your system is probably storing the sar output for 30 days. Ours is stored in /var/adm/sa as saDD where DD is the day of the month. Your location may be different. If you find the archived sar files use ‘sar -f filename’ to view a specific file.
You can also get information from sar about your calls, kernel, paging, etc.
You could also use vmstat to get memory, paging, faults and cpu usage.
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