Is this even possible in PHP?
If not, what is the highest precision available?
The microtime
function is what you're looking for.
PHP does not supply a function that has higher precision than microseconds.
You can use the system
function to get the value straight from the machine if you are running Linux:
$nanotime = system('date +%s%N');
%s
is the amount of seconds, appended by %N
, which is the amount of nanoseconds.