nodejs javascript resolution library performance typescript date milliseconds performance-metrics performance-tuning performance-analysis performance-monitoring browsers seconds performance-testing nanoseconds nanosecond-resolution hrtime microseconds date-now

nodejs javascript resolution library performance typescript date milliseconds performance-metrics performance-tuning performance-analysis performance-monitoring browsers seconds performance-testing nanoseconds nanosecond-resolution hrtime microseconds date-now

linux unix time date milliseconds posix now utc timestamp gmt seconds epoch second millis 1970 date-now unix-epoch posix-epoch