From 3259877d3563ac022633fbd8b73134a10567331e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= Date: Sun, 9 Dec 2012 23:52:59 +0100 Subject: [PATCH] store: Add GC-related operations. * guix/store.scm (gc-action): New enumerate type. (read-long-long, read-string-list, write-store-path, write-store-path-list, read-store-path-list): New procedures. (write-arg): Add support for `store-path' and `store-path-list'. (read-arg): Add support for `store-path-list'. (define-operation): Add support for multiple-value returns. (run-gc, live-paths, dead-paths, collect-garbage, delete-paths): New procedures. (%long-long-max): New macro. * tests/store.scm: New file. * Makefile.am (TESTS): Add it. --- Makefile.am | 1 + guix/store.scm | 102 ++++++++++++++++++++++++++++++++++++++++++++++-- tests/store.scm | 87 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 186 insertions(+), 4 deletions(-) create mode 100644 tests/store.scm diff --git a/Makefile.am b/Makefile.am index d52bd389be..7c33fe4b14 100644 --- a/Makefile.am +++ b/Makefile.am @@ -176,6 +176,7 @@ TESTS = \ tests/build-utils.scm \ tests/packages.scm \ tests/snix.scm \ + tests/store.scm \ tests/union.scm \ tests/guix-build.sh \ tests/guix-download.sh \ diff --git a/guix/store.scm b/guix/store.scm index 67620a1767..204364f319 100644 --- a/guix/store.scm +++ b/guix/store.scm @@ -50,8 +50,14 @@ add-text-to-store add-to-store build-derivations + add-temp-root add-indirect-root + live-paths + dead-paths + collect-garbage + delete-paths + current-build-output-port %store-prefix @@ -111,8 +117,16 @@ (sha1 2) (sha256 3)) +(define-enumerate-type gc-action + ;; store-api.hh + (return-live 0) + (return-dead 1) + (delete-dead 2) + (delete-specific 3)) + (define %nix-state-dir (or (getenv "NIX_STATE_DIR") "/nix/var/nix")) + (define %default-socket-path (string-append %nix-state-dir "/daemon-socket/socket")) @@ -133,6 +147,10 @@ (bytevector-u64-set! b 0 n (endianness little)) (put-bytevector p b))) +(define (read-long-long p) + (let ((b (get-bytevector-n p 8))) + (bytevector-u64-ref b 0 (endianness little)))) + (define write-padding (let ((zero (make-bytevector 8 0))) (lambda (n p) @@ -159,9 +177,23 @@ (write-int (length l) p) (for-each (cut write-string <> p) l)) +(define (read-string-list p) + (let ((len (read-int p))) + (unfold (cut >= <> len) + (lambda (i) + (read-string p)) + 1+ + 0))) + +(define (write-store-path f p) + (write-string f p)) ; TODO: assert path + (define (read-store-path p) (read-string p)) ; TODO: assert path +(define write-store-path-list write-string-list) +(define read-store-path-list read-string-list) + (define (write-contents file p) "Write the contents of FILE to output port P." (define (dump in size) @@ -223,7 +255,8 @@ (write-string ")" p)))) (define-syntax write-arg - (syntax-rules (integer boolean file string string-list base16) + (syntax-rules (integer boolean file string string-list + store-path store-path-list base16) ((_ integer arg p) (write-int arg p)) ((_ boolean arg p) @@ -234,11 +267,15 @@ (write-string arg p)) ((_ string-list arg p) (write-string-list arg p)) + ((_ store-path arg p) + (write-store-path arg p)) + ((_ store-path-list arg p) + (write-store-path-list arg p)) ((_ base16 arg p) (write-string (bytevector->base16-string arg) p)))) (define-syntax read-arg - (syntax-rules (integer boolean string store-path base16) + (syntax-rules (integer boolean string store-path store-path-list base16) ((_ integer p) (read-int p)) ((_ boolean p) @@ -247,6 +284,8 @@ (read-string p)) ((_ store-path p) (read-store-path p)) + ((_ store-path-list p) + (read-store-path-list p)) ((_ hash p) (base16-string->bytevector (read-string p))))) @@ -385,7 +424,7 @@ again until #t is returned or an error is raised." (define-syntax define-operation (syntax-rules () - ((_ (name (type arg) ...) docstring return) + ((_ (name (type arg) ...) docstring return ...) (define (name server arg ...) docstring (let ((s (nix-server-socket server))) @@ -395,7 +434,7 @@ again until #t is returned or an error is raised." ;; Loop until the server is done sending error output. (let loop ((done? (process-stderr server))) (or done? (loop (process-stderr server)))) - (read-arg return s)))))) + (values (read-arg return s) ...)))))) (define-operation (valid-path? (string path)) "Return #t when PATH is a valid store path." @@ -436,6 +475,61 @@ name--it is the caller's responsibility to ensure that it is an absolute file name. Return #t on success." boolean) +(define (run-gc server action to-delete min-freed) + "Perform the garbage-collector operation ACTION, one of the +`gc-action' values. When ACTION is `delete-specific', the TO-DELETE is +the list of store paths to delete. IGNORE-LIVENESS? should always be +#f. MIN-FREED is the minimum amount of disk space to be freed, in +bytes, before the GC can stop. Return the list of store paths delete, +and the number of bytes freed." + (let ((s (nix-server-socket server))) + (write-int (operation-id collect-garbage) s) + (write-int action s) + (write-store-path-list to-delete s) + (write-arg boolean #f s) ; ignore-liveness? + (write-long-long min-freed s) + (write-int 0 s) ; obsolete + (when (>= (nix-server-minor-version server) 5) + ;; Obsolete `use-atime' and `max-atime' parameters. + (write-int 0 s) + (write-int 0 s)) + + ;; Loop until the server is done sending error output. + (let loop ((done? (process-stderr server))) + (or done? (loop (process-stderr server)))) + + (let ((paths (read-store-path-list s)) + (freed (read-long-long s)) + (obsolete (read-long-long s))) + (values paths freed)))) + +(define-syntax-rule (%long-long-max) + ;; Maximum unsigned 64-bit integer. + (- (expt 2 64) 1)) + +(define (live-paths server) + "Return the list of live store paths---i.e., store paths still +referenced, and thus not subject to being garbage-collected." + (run-gc server (gc-action return-live) '() (%long-long-max))) + +(define (dead-paths server) + "Return the list of dead store paths---i.e., store paths no longer +referenced, and thus subject to being garbage-collected." + (run-gc server (gc-action return-dead) '() (%long-long-max))) + +(define* (collect-garbage server #:optional (min-freed (%long-long-max))) + "Collect garbage from the store at SERVER. If MIN-FREED is non-zero, +then collect at least MIN-FREED bytes. Return the paths that were +collected, and the number of bytes freed." + (run-gc server (gc-action delete-dead) '() min-freed)) + +(define* (delete-paths server paths #:optional (min-freed (%long-long-max))) + "Delete PATHS from the store at SERVER, if they are no longer +referenced. If MIN-FREED is non-zero, then stop after at least +MIN-FREED bytes have been collected. Return the paths that were +collected, and the number of bytes freed." + (run-gc server (gc-action delete-specific) paths min-freed)) + ;;; ;;; Store paths. diff --git a/tests/store.scm b/tests/store.scm new file mode 100644 index 0000000000..71f68a1f23 --- /dev/null +++ b/tests/store.scm @@ -0,0 +1,87 @@ +;;; Guix --- Nix package management from Guile. -*- coding: utf-8 -*- +;;; Copyright (C) 2012 Ludovic Courtès +;;; +;;; This file is part of Guix. +;;; +;;; 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. +;;; +;;; 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 Guix. If not, see . + + +(define-module (test-store) + #:use-module (guix store) + #:use-module (guix utils) + #:use-module (guix base32) + #:use-module (distro packages bootstrap) + #:use-module (ice-9 match) + #:use-module (srfi srfi-1) + #:use-module (srfi srfi-11) + #:use-module (srfi srfi-64)) + +;; Test the (guix store) module. + +(define %store + (false-if-exception (open-connection))) + +(when %store + ;; Make sure we build everything by ourselves. + (set-build-options %store #:use-substitutes? #f)) + +(define %seed + (seed->random-state (logxor (getpid) (car (gettimeofday))))) + +(define (random-text) + (number->string (random (expt 2 256) %seed) 16)) + + +(test-begin "store") + +(test-skip (if %store 0 10)) + +(test-assert "dead-paths" + (let ((p (add-text-to-store %store "random-text" + (random-text) '()))) + (member p (dead-paths %store)))) + +;; FIXME: Find a test for `live-paths'. +;; +;; (test-assert "temporary root is in live-paths" +;; (let* ((p1 (add-text-to-store %store "random-text" +;; (random-text) '())) +;; (b (add-text-to-store %store "link-builder" +;; (format #f "echo ~a > $out" p1) +;; '())) +;; (d1 (derivation %store "link" (%current-system) +;; "/bin/sh" `("-e" ,b) '() +;; `((,b) (,p1)))) +;; (p2 (derivation-path->output-path d1))) +;; (and (add-temp-root %store p2) +;; (build-derivations %store (list d1)) +;; (valid-path? %store p1) +;; (member (pk p2) (live-paths %store))))) + +(test-assert "dead path can be explicitly collected" + (let ((p (add-text-to-store %store "random-text" + (random-text) '()))) + (let-values (((paths freed) (delete-paths %store (list p)))) + (and (equal? paths (list p)) + (> freed 0) + (not (file-exists? p)))))) + +(test-end "store") + + +(exit (= (test-runner-fail-count (test-runner-current)) 0)) + +;;; Local Variables: +;;; eval: (put 'test-assert 'scheme-indent-function 1) +;;; End: