Some OS level threshold for performance.
Run queue > 8 : May indicate an overloaded CPU.
Page_in and Page_out > 50 : May indicate overloaded RAM memory. This should be correlated with page-outs and scan rate.
user+system CPU > 70% : Indicates periods with a fully-loaded CPU subssystem.Periods of 100% utilization are only a concern when runqueue values exceeds the number of CPUs on the server.