In order to set optimal values to MaxClients or MaxRequestWorkers we have to know how much memory apache consumes for each process. The script below give you Maximum memory usage of a single process and average memory usage of each process. But the values change under server load. So, stress test your server to fill up the memory to set correct values. This won’t give you the exact/absolute value but does most of the job.Setting values between average and max should save you.