Re: [Boost-users] [timer] Comments do not match the implementation?

From: Jeff Garland (jeff_at_[hidden])
Date: 2006-09-17 14:27:49

KSpam wrote:
> I would like to use boost::timer to replace a timing object from another 
> library.  In looking into the header file, I noticed the following comments:
> 
> //  It is recommended that implementations measure wall clock rather than CPU
> //  time since the intended use is performance measurement on systems where
> //  total elapsed time is more important than just process or CPU time.
> 
> All is well and good I thought to myself ... wall clock is exactly what I 
> want!  But alas, the implementation just wraps std::clock().  The man page 
> for clock states the following:
> 
> "The clock() function returns an approximation of processor time used by the 
> program."
> 
> In summary, the header states that the timer implementation should use wall 
> clock time, but it ignores its own advice and uses processor time.  I'm 
> confused.  Do I need to create my own timer implementation in order to use 
> wall clock time?

No, there's a couple of date-time based timers floating around that measure 
wall clock time.  You can find the most recent incarnation in the super_string 
(version 2) download in the vault

http://boost-consulting.com/vault/index.php?&direction=0&order=&directory=Strings%20-%20Text%20Processing

The code is in test/date_time_timer.hpp and you'll find some example usage in 
test/performance.cpp.  Usage should be pretty obvious.

The long running goal has been to replace the current timer with something 
like the one above...it just hasn't been high enough on the priority list to 
get done yet.

Jeff