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Hope the link below helps in better understanding server performance. There is a good section on background process ( cut and paste below ) and also best practices when considering your deployment.
A single background process can consume 100% of a single CPU core, and sometimes even more for certain tasks. As a result of this, the total number of instances you should run depends on the machine’s available cores—as well as on what you’re trying to improve. The deployment examples below uses N
to represent the machine’s total number of cores, and each suggests a different strategy where the background process is concerned. When in doubt, start with the low end of the suggested range and assess performance before increasing the number.