mjhjmtu

ConTeXt provides a macro testfeatureonce to benchmark performance. The syntax is

testfeatureoncen...

which runs the code in the second argument n times (n is assumed to be an integer) and stores the elapsed time (in seconds) in the macro elapasedtime. The following diagnostic message is also printed on the terminal:

system > starting feature test (n=1)
system > 1 feature tests done (1.353s)


Here is a minimal ConTeXt document showing it's usage:

starttext

testfeatureonce1000
 setbox0hbox
 startMPcode draw (0,0) -- (1cm, 1cm); stopMPcode

elapsedtime
stoptext

What is the functionally equivalent macro in LaTeX used for benchmarking performance?

With pdfTeX you can simulate the behaviour using pdfresettimer and pdfelapsedtime. I used some expl3 wrappers to make the same syntax as the ConTeXt version.

documentclassarticle
usepackagexparse
usepackagetikz

%% For LuaTeX
% defpdfresettimerdirectluapdfelapsedtimer_basetime = os.clock()
% defpdfelapsedtimedirectluatex.print((os.clock()-pdfelapsedtimer_basetime)*65536)
%%

ExplSyntaxOn
cs_set_eq:NN __tfo_start_timer: pdfresettimer
cs_set_eq:NN __tfo_elapsed_time: pdfelapsedtime
cs_new:Npn __tfo_output:n #1
 
 iow_term:x
 
 >~#1~feature~tests~done~
 (fp_eval:n round ( __tfo_elapsed_time: / 65536 , 3 ) s)
 
 
cs_new:Npn __tfo_run_n_times:nn #1 #2
 
 if_int_compare:w #1 > 0 scan_stop:
 exp_after:wN __tfo_run_n_times:nn
 exp_after:wN int_value:w __int_eval:w #1 - 1 #2 
 fi:
 
NewDocumentCommandTestFeatureOnce
 m m 
 
 __tfo_start_timer:
 __tfo_run_n_times:nn #1 #2 
 __tfo_output:n #1 
 
ExplSyntaxOff

begindocument

TestFeatureOnce1000
 setbox0hbox
 tikz draw (0,0) -- (1cm, 1cm);

enddocument

For LuaTeX I used the code from this post (which is also implemented in pdftexcmds). However I used a slightly modified version that does not use a protecteddef to allow the returned pdfelapsedtime to be f-expanded by l3fp.

I don't know if this is possible in XeTeX without resorting to system commands...

For all I know, there's no such macro in the LaTeX2e base (perhaps LaTeX3 has something equivalent?). But we can look up the definition of testfeatureonce in the ConTeXt source code. The relevant definitions are in the syst-aux module.

That implementation makes use of the eTeX primitives pdfresettimer and pdfelapsedtime to reset an internal timer and get the elapsed time since the last reset, respectively. I didn't find a proper source for this, but it seems 65536 equals one second in the value returned by pdfelapsedtime.

A reimplementation in pure LaTeX code might look like this:

documentclassarticle
usepackagetikz

makeatletter
letresettimer=pdfresettimer
letelapsedtime=pdfelapsedtime

newcountc@syst@helpers@test@feature@n
newcountc@syst@helpers@test@feature@m

newcommandtestfeature[2]%
 c@syst@helpers@test@feature@m=#1relax
 defsyst@helpers@test@feature@step%
 advancec@syst@helpers@test@feature@n by 1relax
 ifnumc@syst@helpers@test@feature@n>c@syst@helpers@test@feature@melse
 #2expandaftersyst@helpers@test@feature@step
 fi
 %
 retestfeature


newcommandretestfeature
 bgroup
 ifcaseinteractionmode letwaitrelax fi
 resettimer
 c@syst@helpers@test@feature@n=0relax
 syst@helpers@test@feature@step
 wait
 egroup


newcommandtestfeatureonce[2]%
 begingroup
 letwaitrelax
 testfeature#1#2%
 endgroup


makeatother

begindocument

testfeatureonce1000
 setbox0hbox
 tikz draw (0,0) -- (1cm, 1cm); 

theelapsedtime

enddocument