It means server could randomly freeze., what to do?

You should check your server sensors with lm_sensors or reboot server and check some BIOS information about CPU temperatures or you can just feel with your hand if CPU fan is warm.

If you see this, its not normal:

Aug 11 02:36:27 tvandmovies kernel: [354969.654819] CPU2: Temperature above threshold, cpu clock throttled (total events = 33273076)
Aug 11 02:36:27 tvandmovies kernel: [354969.654819] CPU0: Temperature above threshold, cpu clock throttled (total events = 33273080)
Aug 11 02:41:27 tvandmovies kernel: [355274.041807] CPU2: Temperature above threshold, cpu clock throttled (total events = 33321213)
Aug 11 02:41:27 tvandmovies kernel: [355274.041807] CPU1: Temperature/speed normal
Aug 11 02:41:27 tvandmovies kernel: [355274.041807] CPU3: Temperature/speed normal
Aug 11 02:41:27 tvandmovies kernel: [355274.041807] CPU0: Temperature above threshold, cpu clock throttled (total events = 33321217)
Aug 11 02:46:49 tvandmovies kernel: [355601.753974] CPU1: Temperature/speed normal
Aug 11 02:46:49 tvandmovies kernel: [355601.753974] CPU3: Temperature/speed normal
Aug 11 02:46:49 tvandmovies kernel: [355601.753974] CPU2: Temperature above threshold, cpu clock throttled (total events = 33353604)
Aug 11 02:46:49 tvandmovies kernel: [355601.754219] CPU0: Temperature above threshold, cpu clock throttled (total events = 33353607)
Aug 11 02:56:12 tvandmovies kernel: [356171.441703] CPU3: Temperature/speed normal
Aug 11 02:56:12 tvandmovies kernel: [356171.441703] CPU1: Temperature/speed normal
Aug 11 02:56:12 tvandmovies kernel: [356171.441703] CPU2: Temperature above threshold, cpu clock throttled (total events = 33355515)
Aug 11 02:56:12 tvandmovies kernel: [356171.441703] CPU0: Temperature above threshold, cpu clock throttled (total events = 33355518)