guix/guix/profiling.scm

76 lines
2.5 KiB
Scheme
Raw Normal View History

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2017, 2019 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix profiling)
#:use-module (ice-9 match)
#:autoload (ice-9 format) (format)
#:export (profiled?
register-profiling-hook!))
;;; Commentary:
;;;
;;; Basic support for Guix-specific profiling.
;;;
;;; Code:
(define profiled?
(let ((profiled
(or (and=> (getenv "GUIX_PROFILING") string-tokenize)
'())))
(lambda (component)
"Return true if COMPONENT profiling is active."
(member component profiled))))
(define %profiling-hooks
;; List of profiling hooks.
(map (match-lambda
("after-gc" after-gc-hook)
((or "exit" #f) exit-hook))
(or (and=> (getenv "GUIX_PROFILING_EVENTS") string-tokenize)
'("exit"))))
(define (register-profiling-hook! component thunk)
"Register THUNK as a profiling hook for COMPONENT, a string such as
\"rpc\"."
(when (profiled? component)
(for-each (lambda (hook)
(add-hook! hook thunk))
%profiling-hooks)))
(define (show-gc-stats)
"Display garbage collection statistics."
(define MiB (* 1024 1024.))
(define stats (gc-stats))
(format (current-error-port) "Garbage collection statistics:
heap size: ~,2f MiB
allocated: ~,2f MiB
GC times: ~a
time spent in GC: ~,2f seconds (~d% of user time)~%"
(/ (assq-ref stats 'heap-size) MiB)
(/ (assq-ref stats 'heap-total-allocated) MiB)
(assq-ref stats 'gc-times)
(/ (assq-ref stats 'gc-time-taken)
internal-time-units-per-second 1.)
(inexact->exact
(round (* (/ (assq-ref stats 'gc-time-taken)
(tms:utime (times)) 1.)
100)))))
(register-profiling-hook! "gc" show-gc-stats)