drake (version 5.0.0)

rate_limiting_times: Return a data frame of elapsed build times of the rate-limiting targets of a drake project.

Description

This function produces a conservative estimate for predict_runtime() for when parallel computing is used in make(). This feature is experimental. The accuracy, precision, and utility of these supposedly rate-limiting times has not been confirmed by rigorous performance studies.

Usage

rate_limiting_times(config, targets = NULL, from_scratch = FALSE,
  targets_only = FALSE, future_jobs = 1, digits = 3)

Arguments

config

option internal runtime parameter list of make(...), produced by both make() and drake_config().

targets

Character vector, names of targets. Find the rate-limiting times for building these targets plus dependencies. Defaults to all targets.

from_scratch

logical, whether to assume next hypothetical call to make() is a build from scratch (after clean()).

targets_only

logical, whether to factor in just the targets or use times from everything, including the imports.

future_jobs

hypothetical number of jobs assumed for the predicted runtime. assuming this number of jobs.

digits

number of digits for rounding the times.

Value

A data frame of times of the worst-case scenario rate-limiting targets in each parallelizable stage.

Details

The stage column of the returned data frame is an index that denotes a parallelizable stage. Within each stage during make(), the targets are divided among the available jobs. For rate_limiting_times(), we assume the targets are divided evenly among the jobs and one job gets all the slowest targets. The build times of this hypothetical pessimistic job are returned for each stage.

By default from_scratch is FALSE. That way, rate_limiting_times() takes into account that some targets are already up to date, meaning their elapsed build times will be instant during the next make().

For the results to make sense, the previous build times of all targets need to be available (automatically cached by make()). Otherwise, rate_limiting_times() will warn you and tell you which targets have missing times.

See Also

predict_runtime, build_times make

Examples

# NOT RUN {
test_with_dir("Quarantine side effects.", {
load_basic_example() # Get the code with drake_example("basic").
config <- make(my_plan) # Run the project, build the targets.
rate_limiting_times(config) # Everything is up to date.
# Assume everything runs from scratch with 1 job.
rate_limiting_times(config, from_scratch  = TRUE, digits = 4)
# With 2 jobs, some of the targets are not rate-limiting.
rate_limiting_times(
  config,
  future_jobs = 2,
  from_scratch = TRUE,
  digits = 4
)
# Find the rate-limiting times of just building targets
# "small" and "large".
rate_limiting_times(
  config,
  targets = c("small", "large"),
  from_scratch = TRUE,
  digits = 4
)
})
# }
# NOT RUN {
# }