Rprof {utils}R Documentation

Enable Profiling of R's Execution

Description

Enable or disable profiling of the execution of R expressions.

Usage

Rprof(filename = "Rprof.out", append = FALSE, interval = 0.02)

Arguments

filename The file to be used for recording the profiling results. Set to NULL or "" to disable profiling.
append logical: should the file be over-written or appended to?
interval real: time interval between samples.

Details

Enabling profiling automatically disables any existing profiling to another or the same file.

Profiling works by writing out the call stack every interval seconds, to the file specified. Either the summaryRprof function or the Perl script R CMD Rprof can be used to process the output file to produce a summary of the usage; use R CMD Rprof --help for usage information.

Exactly what the time interval measures is subtle: it is time that the R process is running and executing an R command. It is not however just CPU time, for if readline() is waiting for input, that counts (on Windows, but not on Unix).

Note that the timing interval cannot be too small, for the time spent in each profiling step is added to the interval. What is feasible is machine-dependent, but 10ms seems as small as advisable on a 1GHz machine.

Note

Using R CMD Rprof needs Windows Perl to be installed.

See Also

The chapter on “Tidying and profiling R code” in “Writing R Extensions” (see the ‘doc/manual’ subdirectory of the R source tree).

summaryRprof

Examples

## Not run: 
Rprof()
## some code to be profiled
Rprof(NULL)
## some code NOT to be profiled
Rprof(append=TRUE)
## some code to be profiled
Rprof(NULL)
...
## Now post-process the output as described in Details
## End(Not run)

[Package utils version 2.1.0 Index]