unix/Sys.cpuinfo: Provide Information about the Linux Hardware (CPU, Memory,...

In sfsmisc: Utilities from 'Seminar fuer Statistik' ETH Zurich

Provide Information about the Linux Hardware (CPU, Memory, etc)

Description

Return information about the Linux hardware, notably the CPU (the central processor unit) and memory of the computer R is running on. This is currently only available for Linux.

These functions exist on other unix-alike platforms, but produce an error when called.

Usage

Sys.procinfo(procfile)
Sys.cpuinfo()
Sys.meminfo()
Sys.memGB(kind = "MemTotal")
Sys.MIPS()

Arguments

Value

The Sys.*info() functions return a "simple.list", here basically a named character vector, (where the names have been filtered through make.names(*, unique=TRUE) which is of importance for multi-processor or multi-core CPUs, such that vector can easily be indexed.

Sys.memGB() returns available memory in giga bytes [GB];
Sys.MIPS() returns a number giving an approximation of the Million Iinstructions Per Second that the CPU processes (using “bogomips”). This is a performance measure of the basic non-numeric processing capabilities. For single-core Linux systems, often about twice the basic clock rate in “MHz” (as available by Sys.cpuinfo()["cpu.MHz"]); now, with multicore systems, the result is often around (but smaller than) 2 * #{cores} * clock.rate.

Note

These currently do rely on the Linux ‘/proc/’ file system, and may not easily be portable to non-Linux environments.

On multi-processor machines, Sys.cpuinfo() contains each field for each processor (i.e., names(Sys.cpuinfo()) has duplicated entries).

Conceivably, the bogoMIPS source code is open and available and could be built into R.

Author(s)

Martin Maechler

See Also

Sys.ps, etc.

Examples

(n.cores <- parallel::detectCores())
if(substr(R.version[["os"]], 1,5) == "linux") { ##-- only on Linux
  Sys.cpuinfo() # which is often ugly; this looks much better:
  length(Sys.cpu2 <- local({I <- Sys.cpuinfo(); I[ !grepl("^flags", names(I)) ] }))
  ## may still be too much, notably if n.cores > 2:
  (Sys3 <- Sys.cpu2[!grepl("[.][0-9]+$", names(Sys.cpu2))])

  Sys.MIPS() ## just the 'bogomips' from above:
  Sys.MIPS() / as.numeric(Sys.cpuinfo()["cpu.MHz"]) ## ~~ 2 * #{cores} ((no longer))

  ## Available Memory -- can be crucial:
  Sys.memGB() #- default "MemTotal"
  if(Sys.memGB("MemFree") > 16)
     message("Be happy! You have more than 16 Gigabytes of free memory")
}