More Detailed Timing than Time::HiRes' clock method

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi,
Is there any way to get finer timing output than Time::HiRes, say upto nano/milisecond?. My code below:

#!/usr/bin/perl -w

use Time::HiRes qw(clock); # version 1.90

my $start_time = clock();

$line++ while (<>);   # Count number of lines in the file(s)

my $end_time = clock();
my $difference = $end_time - $start_time;

print ("It took ", $difference, " second\n");
[download]

Gives:

It took 0.02 second
[download]

Which is not refined enough to me.

Comment on More Detailed Timing than Time::HiRes' clock method Select or Download Code

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Re: More Detailed Timing than Time::HiRes' clock method by liverpole (Monsignor) on Sep 26, 2006 at 12:43 UTC
How about using tv_interval? ... `#!/usr/bin/perl -w use strict; use warnings; use Time::HiRes qw( gettimeofday tv_interval ); my $start = [gettimeofday]; my $line; $line++ while (<>); # Count number of lines in the file(s) my $end = [gettimeofday]; my $difference = tv_interval($start, $end); print "It took ", $difference, " second\n";` [download] which gives something like: `It took 0.000103 second` [download] s''(q.S:$/9=(T1';s;(..)(..);$..=substr+crypt($1,$2),2,3;eg;print$..$/	[reply] [d/l] [select]
Re: More Detailed Timing than Time::HiRes' clock method by McDarren (Abbot) on Sep 26, 2006 at 12:50 UTC
Have you even looked at the documentation for Time::HiRes? `$your_code =~ s/clock/time/g;` ...and then you should get something like: `perl nano foo.pl It took 0.01027512550354 second` [download]	[reply] [d/l] [select]
Re^2: More Detailed Timing than Time::HiRes' clock method by Anonymous Monk on Sep 27, 2006 at 01:52 UTC
McDarren, How can you use 'nano' there? Cause when I followed your suggestion and calling 'nano' it gives me: `Can't open perl script "nano": No such file or directory.` [download] Nevertheless, without nano it prints the refined results though. BTW also, what is the difference between time() as used by you versus liverpole's suggestion of using 'tv_interval' and 'gettimeofday'?	[reply] [d/l]
Re^3: More Detailed Timing than Time::HiRes' clock method by McDarren (Abbot) on Sep 27, 2006 at 03:10 UTC
"How can you use 'nano' there?..." I think perhaps my example was a little misleading. "nano" is the name of the script, and "foo.pl" is the name of the file being precessed. Think of it instead as: `perl nano some_random_file` [download] ..and it should make more sense. "..what is the difference between time() as used by you versus liverpole's suggestion of using 'tv_interval' and 'gettimeofday'?" Again, rtfm. As far as I can see, there is no real difference. The resolution that you get will be mostly system-dependant. Cheers, Darren	[reply] [d/l]