R: Benchmark a series of functions

mark {bench}

R Documentation

Benchmark a series of functions

Description

Benchmark a list of quoted expressions. Each expression will always run at least twice, once to measure the memory allocation and store results and one or more times to measure timing.

Usage

mark(
  ...,
  min_time = 0.5,
  iterations = NULL,
  min_iterations = 1,
  max_iterations = 10000,
  check = TRUE,
  memory = capabilities("profmem"),
  filter_gc = TRUE,
  relative = FALSE,
  time_unit = NULL,
  exprs = NULL,
  env = parent.frame()
)

Arguments

`...`	Expressions to benchmark, if named the `expression` column will be the name, otherwise it will be the deparsed expression.
`min_time`	The minimum number of seconds to run each expression, set to `Inf` to always run `max_iterations` times instead.
`iterations`	If not `NULL`, the default, run each expression for exactly this number of iterations. This overrides both `min_iterations` and `max_iterations`.
`min_iterations`	Each expression will be evaluated a minimum of `min_iterations` times.
`max_iterations`	Each expression will be evaluated a maximum of `max_iterations` times.
`check`	Check if results are consistent. If `TRUE`, checking is done with `all.equal()`, if `FALSE` checking is disabled and results are not stored. If `check` is a function that function will be called with each pair of results to determine consistency.
`memory`	If `TRUE` (the default when R is compiled with memory profiling), track memory allocations using `utils::Rprofmem()`. If `FALSE` disable memory tracking.
`filter_gc`	If `TRUE` remove iterations that contained at least one garbage collection before summarizing. If `TRUE` but an expression had a garbage collection in every iteration, filtering is disabled, with a warning.
`relative`	If `TRUE` all summaries are computed relative to the minimum execution time rather than absolute time.
`time_unit`	If `NULL` the times are reported in a human readable fashion depending on each value. If one of 'ns', 'us', 'ms', 's', 'm', 'h', 'd', 'w' the time units are instead expressed as nanoseconds, microseconds, milliseconds, seconds, hours, minutes, days or weeks respectively.
`exprs`	A list of quoted expressions. If supplied overrides expressions defined in `...`.
`env`	The environment which to evaluate the expressions

Value

A tibble with the additional summary columns. The following summary columns are computed

expression - bench_expr The deparsed expression that was evaluated (or its name if one was provided).
min - bench_time The minimum execution time.
median - bench_time The sample median of execution time.
itr/sec - double The estimated number of executions performed per second.
mem_alloc - bench_bytes Total amount of memory allocated by R while running the expression. Memory allocated outside the R heap, e.g. by malloc() or new directly is not tracked, take care to avoid misinterpreting the results if running code that may do this.
gc/sec - double The number of garbage collections per second.
n_itr - integer Total number of iterations after filtering garbage collections (if filter_gc == TRUE).
n_gc - double Total number of garbage collections performed over all iterations. This is a psudo-measure of the pressure on the garbage collector, if it varies greatly between to alternatives generally the one with fewer collections will cause fewer allocation in real usage.
total_time - bench_time The total time to perform the benchmarks.
result - list A list column of the object(s) returned by the evaluated expression(s).
memory - list A list column with results from Rprofmem().
time - list A list column of bench_time vectors for each evaluated expression.
gc - list A list column with tibbles containing the level of garbage collection (0-2, columns) for each iteration (rows).

Examples

dat <- data.frame(x = runif(100, 1, 1000), y=runif(10, 1, 1000))
mark(
  min_time = .1,

  dat[dat$x > 500, ],
  dat[which(dat$x > 500), ],
  subset(dat, x > 500))