The performance of a MacBook Pro laptop running OS X 10.8.5, aka "Mountain Lion", that I've been using was very poor today and the fan was making much more noise than usual. When I used
top -o cpuand the Activity Monitor to check which process was causing the problem, I found that the Symantec SymDaemon process was the culprit. After I killed that process, performance improved considerably, the fan noise subsided and when I compared the CPU temperature before and after stopping the process with osx-cpu-temp, I found the CPU was considerably cooler afterwards. Likewise, when I checked the fan speed with smcFanControl before and aftwards, I found that smcFanControl showed the fans to be running considerably slower after the process was stopped.
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