Mtime_clockMonotonic time clock.
Mtime_clock provides access to a system monotonic clock. This time increases monotonically and is not subject to operating system calendar time adjustments.
Only use Mtime_clock.now if you need inter-process time correlation, otherwise prefer Mtime_clock.elapsed and counters.
Consult important information about error handling and platform support.
val elapsed : unit -> Mtime.spanelapsed () is the monotonic time span elapsed since the beginning of the program.
Raises Sys_error, see error handling
val now : unit -> Mtime.tnow () is the current system-relative monotonic timestamp. Its absolute value is meaningless.
Raises Sys_error, see error handling
val period : unit -> Mtime.span optionperiod () is the clock's period as a monotonic time span (if available).
val counter : unit -> countercounter () is a counter counting from now on.
Raises Sys_error, see error handling
val count : counter -> Mtime.spancount c is the monotonic time span elapsed since c was created.
elapsed_ns () is the unsigned 64-bit integer nanosecond monotonic time span elapsed since the beginning of the program.
Raises Sys_error, see error handling
now_ns () is an unsigned 64-bit integer nanosecond system-relative monotonic timestamp. The absolute value is meaningless.
Raises Sys_error, see error handling
period_ns () is the clock's period as an unsigned 64-bit integer nanosecond monotonic time span (if available).
The functions elapsed, now, counter, elapsed_ns and now_ns raise Sys_error whenever they can't determine the current time or that it doesn't fit in Mtime's range. Usually this exception should only be catched at the toplevel of your program to log it and abort the program. It indicates a serious error condition in the system.
All the other functions, whose functionality is less essential, simply silently return None if they can't determine the information either because it is unavailable or because an error occured.
clock_gettime with CLOCK_BOOTTIME. This means that sleep time is taken into account.clock_gettime with CLOCK_MONOTONIC.mach_continous_time. This means that sleep time is taken into account.performance.now (consult availability) which returns a double floating point value in milliseconds with resolution up to the microsecond.perf_hooks module, which provides an interface compatible to the performance module in browsers.