profmem {profmem} | R Documentation |
profmem()
evaluates and memory profiles an R expression.
profmem_begin()
starts the memory profiling of all the following R
evaluations until profmem_end()
is called.
profmem_suspend()
suspends an active profiling until resumed by
profmem_resume()
or ended by profmem_end()
.
Calling profmem_begin()
or profmem()
will resume any suspended
profiling. Nested resuming and suspending is not supported;
it is a global state.
profmem_status()
checks whether there is an active profmem session
or not, and whether it is suspended or not.
profmem_depth()
gets the number of nested / stacked profmem sessions.
profmem(expr, envir = parent.frame(), substitute = TRUE, threshold = getOption("profmem.threshold", 0L)) profmem_begin(threshold = getOption("profmem.threshold", 0L)) profmem_end() profmem_suspend() profmem_resume() profmem_status() profmem_depth()
expr |
An R expression to be evaluated and profiled. |
envir |
The environment in which the expression should be evaluated. |
substitute |
Should |
threshold |
The smallest memory allocation (in bytes) to log. |
In order for memory profiling to work, R must have been built with memory
profiling enabled. Function
base::capabilities("profmem")
will
return TRUE
of it is enabled, otherwise FALSE
.
If memory profiling is not supported, profmem()
and profmem_begin()
will produce an informative error. The pre-built R binaries on
CRAN support memory profiling.
What is logged? The profmem()
function uses utils::Rprofmem()
for
logging memory, which logs all memory allocations that are done via the
R framework. Specifically, the logger is tied to allocVector3()
part
of R's native API. This means that nearly all memory allocations done
in R are logged. Neither memory deallocations nor garbage collection
events are logged. Furthermore, allocations done by non-R native libraries
or R packages that use native code Calloc() / Free()
for internal objects
are also not logged.
Any memory events that would occur due to calling any of the profmem functions themselves will not be logged and not be part of the returned profile data (regardless whether memory profiling is active or not). This is intentional.
If a profmem profiling is already active, profmem()
and profmem_begin()
performs an independent, nested profiling, which has no affect on the
already active one. When the active one completes, it will contain all
memory events also collected by the nested profiling as if the nested one
never occurred.
Profiling gathered by profmem will be corrupted if the code profiled
calls utils::Rprofmem()
, with the exception of such calls done via the
profmem package itself.
profmem()
and profmem_end()
returns the collected
Rprofmem
data.
profmem_begin()
returns (invisibly) the number of nested profmem
session currently active.
profmem_suspend()
and profmem_resume()
returns nothing.
profmem_status()
returns "inactive"
, "active"
,
or "suspended"
.
promem_depth()
returns a non-negative integer.
if (capabilities("profmem")) { ## Memory profile an R expression p <- profmem({ x <- raw(1000) A <- matrix(rnorm(100), ncol = 10) }) ## Display the results print(p) ## Total amount of memory allocation total(p) ## Allocations greater than 1 kB p2 <- subset(p, bytes > 1000) print(p2) ## The expression is evaluated in the calling environment str(x) str(A) }