How to use high-resolution gettimeofday in Perl

In some cases, you may need to measure time in high-resolution, for example, microsecond resolution as provided by gettimeofday() system call. In order to use microsecond-resolution time in Perl, you can use Time::HiRes Perl module which provides gettimeofday() microsecond-resolution timer function.

To install Time::HiRes on Linux, run the following.

$ sudo perl -MCPAN -e ‘install Time::HiRes’

You can measure elapsed time in microsecond resolution as follows.

use Time::HiRes qw( usleep ualarm gettimeofday tv_interval );
my $t0 = [gettimeofday];
[add some computation intensive routine]
my $elapsed = tv_interval ( $t0, [gettimeofday]);
# Or you can get second/microsecond components separately, by using:
my ($seconds, $microseconds) = gettimeofday; // current time

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Dan Nanni is the founder and also a regular contributor of He is a Linux/FOSS enthusiast who loves to get his hands dirty with his Linux box. He likes to procrastinate when he is supposed to be busy and productive. When he is otherwise free, he likes to watch movies and shop for the coolest gadgets.

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