diff options
| -rw-r--r-- | doc/guix.texi | 45 | ||||
| -rw-r--r-- | gnu/packages.scm | 3 | ||||
| -rw-r--r-- | guix/scripts/shell.scm | 161 | ||||
| -rw-r--r-- | guix/transformations.scm | 9 |
4 files changed, 142 insertions, 76 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index 443059147f..876172fa3a 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -5806,17 +5806,6 @@ This is similar to the same-named option in @command{guix package} (@pxref{profile-manifest, @option{--manifest}}) and uses the same manifest files. -@item --rebuild-cache -When using @option{--manifest}, @option{--file}, or when invoked without -arguments, @command{guix shell} caches the environment so that -subsequent uses are instantaneous. The cache is invalidated anytime the -file is modified. - -The @option{--rebuild-cache} forces the cached environment to be -refreshed even if the file has not changed. This is useful if the -@command{guix.scm} or @command{manifest.scm} has external dependencies, -or if its behavior depends, say, on environment variables. - @item --pure Unset existing environment variables when building the new environment, except those specified with @option{--preserve} (see below). This has the effect of @@ -5932,6 +5921,21 @@ directory: guix shell --container --expose=$HOME=/exchange guile -- guile @end example +@item --rebuild-cache +@cindex caching, of profiles +@cindex caching, in @command{guix shell} +In most cases, @command{guix shell} caches the environment so that +subsequent uses are instantaneous. Least-recently used cache entries +are periodically removed. The cache is also invalidated, when using +@option{--file} or @option{--manifest}, anytime the corresponding file +is modified. + +The @option{--rebuild-cache} forces the cached environment to be +refreshed. This is useful when using @option{--file} or +@option{--manifest} and the @command{guix.scm} or @command{manifest.scm} +file has external dependencies, or if its behavior depends, say, on +environment variables. + @item --root=@var{file} @itemx -r @var{file} @cindex persistent environment @@ -5942,11 +5946,20 @@ register it as a garbage collector root. This is useful if you want to protect your environment from garbage collection, to make it ``persistent''. -When this option is omitted, the environment is protected from garbage -collection only for the duration of the @command{guix shell} -session. This means that next time you recreate the same environment, -you could have to rebuild or re-download packages. @xref{Invoking guix -gc}, for more on GC roots. +When this option is omitted, @command{guix shell} caches profiles so +that subsequent uses of the same environment are instantaneous---this is +comparable to using @option{--root} except that @command{guix shell} +takes care of periodically removing the least-recently used garbage +collector roots. + +In some cases, @command{guix shell} does not cache profiles---e.g., if +transformation options such as @option{--with-latest} are used. In +those cases, the environment is protected from garbage collection only +for the duration of the @command{guix shell} session. This means that +next time you recreate the same environment, you could have to rebuild +or re-download packages. + +@xref{Invoking guix gc}, for more on GC roots. @end table @command{guix shell} also supports all of the common build options that diff --git a/gnu/packages.scm b/gnu/packages.scm index ccfc83dd11..65ab7a7c1e 100644 --- a/gnu/packages.scm +++ b/gnu/packages.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2012-2020, 2022 Ludovic Courtès <ludo@gnu.org> ;;; Copyright © 2013 Mark H Weaver <mhw@netris.org> ;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.org> ;;; Copyright © 2016, 2017 Alex Kost <alezost@gmail.com> @@ -51,6 +51,7 @@ %auxiliary-files-path %package-module-path %default-package-module-path + cache-is-authoritative? fold-packages fold-available-packages diff --git a/guix/scripts/shell.scm b/guix/scripts/shell.scm index 546639818f..a92932cbc9 100644 --- a/guix/scripts/shell.scm +++ b/guix/scripts/shell.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2021 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2021-2022 Ludovic Courtès <ludo@gnu.org> ;;; ;;; This file is part of GNU Guix. ;;; @@ -21,7 +21,8 @@ #:use-module ((guix diagnostics) #:select (location)) #:use-module (guix scripts environment) #:autoload (guix scripts build) (show-build-options-help) - #:autoload (guix transformations) (show-transformation-options-help) + #:autoload (guix transformations) (transformation-option-key? + show-transformation-options-help) #:use-module (guix scripts) #:use-module (guix packages) #:use-module (guix profiles) @@ -40,6 +41,7 @@ #:use-module ((guix build utils) #:select (mkdir-p)) #:use-module (guix cache) #:use-module ((ice-9 ftw) #:select (scandir)) + #:autoload (gnu packages) (cache-is-authoritative?) #:export (guix-shell)) (define (show-help) @@ -201,51 +203,35 @@ a hash-prefixed comment, or a blank line." (const #f))) (define (options-with-caching opts) - "If OPTS contains exactly one 'load' or one 'manifest' key, automatically -add a 'profile' key (when a profile for that file is already in cache) or a -'gc-root' key (to add the profile to cache)." - (define (single-file-for-caching opts) - (let loop ((opts opts) - (file #f)) - (match opts - (() file) - ((('package . _) . _) #f) - ((('load . ('package candidate)) . rest) - (and (not file) (loop rest candidate))) - ((('manifest . candidate) . rest) - (and (not file) (loop rest candidate))) - ((('expression . _) . _) #f) - ((_ . rest) (loop rest file))))) - - ;; Check whether there's a single 'load' or 'manifest' option. When that is - ;; the case, arrange to automatically cache the resulting profile. - (match (single-file-for-caching opts) - (#f opts) - (file - (let* ((root (profile-cached-gc-root file)) - (stat (and root (false-if-exception (lstat root))))) - (if (and (not (assoc-ref opts 'rebuild-cache?)) - stat - (<= (stat:mtime ((@ (guile) stat) file)) - (stat:mtime stat))) - (let ((now (current-time))) - ;; Update the atime on ROOT to reflect usage. - (utime root - now (stat:mtime stat) 0 (stat:mtimensec stat) - AT_SYMLINK_NOFOLLOW) - (alist-cons 'profile root - (remove (match-lambda - (('load . _) #t) - (('manifest . _) #t) - (_ #f)) - opts))) ;load right away - (if (and root (not (assq-ref opts 'gc-root))) - (begin - (if stat - (delete-file root) - (mkdir-p (dirname root))) - (alist-cons 'gc-root root opts)) - opts)))))) + "If OPTS contains only options that allow us to compute a cache key, +automatically add a 'profile' key (when a profile for that file is already in +cache) or a 'gc-root' key (to add the profile to cache)." + ;; Attempt to compute a file name for use as the cached profile GC root. + (let* ((root timestamp (profile-cached-gc-root opts)) + (stat (and root (false-if-exception (lstat root))))) + (if (and (not (assoc-ref opts 'rebuild-cache?)) + stat + (<= timestamp (stat:mtime stat))) + (let ((now (current-time))) + ;; Update the atime on ROOT to reflect usage. + (utime root + now (stat:mtime stat) 0 (stat:mtimensec stat) + AT_SYMLINK_NOFOLLOW) + (alist-cons 'profile root + (remove (match-lambda + (('load . _) #t) + (('manifest . _) #t) + (('package . _) #t) + (('ad-hoc-package . _) #t) + (_ #f)) + opts))) ;load right away + (if (and root (not (assq-ref opts 'gc-root))) + (begin + (if stat + (delete-file root) + (mkdir-p (dirname root))) + (alist-cons 'gc-root root opts)) + opts)))) (define (auto-detect-manifest opts) "If OPTS do not specify packages or a manifest, load a \"guix.scm\" or @@ -308,28 +294,87 @@ echo ~a >> ~a (make-parameter (string-append (cache-directory #:ensure? #f) "/profiles"))) -(define (profile-cache-key file) +(define (profile-cache-primary-key) + "Return the \"primary key\" used when computing keys for the profile cache. +Return #f if no such key can be obtained and caching cannot be +performed--e.g., because the package cache is not authoritative." + (and (cache-is-authoritative?) + (match (current-channels) + (() + #f) + (((= channel-commit commits) ...) + (string-join commits))))) + +(define (profile-file-cache-key file system) "Return the cache key for the profile corresponding to FILE, a 'guix.scm' or 'manifest.scm' file, or #f if we lack channel information." - (match (current-channels) - (() #f) - (((= channel-commit commits) ...) + (match (profile-cache-primary-key) + (#f #f) + (primary-key (let ((stat (stat file))) (bytevector->base32-string ;; Since FILE is not canonicalized, only include the device/inode ;; numbers. XXX: In some rare cases involving Btrfs and NFS, this can ;; be insufficient: <https://lwn.net/Articles/866582/>. (sha256 (string->utf8 - (string-append (string-join commits) ":" + (string-append primary-key ":" system ":" (number->string (stat:dev stat)) ":" (number->string (stat:ino stat)))))))))) -(define (profile-cached-gc-root file) - "Return the cached GC root for FILE, a 'guix.scm' or 'manifest.scm' file, or -#f if we lack information to cache it." - (match (profile-cache-key file) - (#f #f) - (key (string-append (%profile-cache-directory) "/" key)))) +(define (profile-spec-cache-key specs system) + "Return the cache key corresponding to SPECS built for SYSTEM, where SPECS +is a list of package specs. Return #f if caching is not possible." + (match (profile-cache-primary-key) + (#f #f) + (primary-key + (bytevector->base32-string + (sha256 (string->utf8 + (string-append primary-key ":" system ":" + (object->string specs)))))))) + +(define (profile-cached-gc-root opts) + "Return two values: the file name of a GC root for use as a profile cache +for the options in OPTS, and a timestamp which, if greater than the GC root's +mtime, indicates that the GC root is stale. If OPTS do not permit caching, +return #f and #f." + (define (key->file key) + (string-append (%profile-cache-directory) "/" key)) + + (let loop ((opts opts) + (system (%current-system)) + (file #f) + (specs '())) + (match opts + (() + (if file + (values (and=> (profile-file-cache-key file system) key->file) + (stat:mtime (stat file))) + (values (and=> (profile-spec-cache-key specs system) key->file) + 0))) + (((and spec ('package . _)) . rest) + (if (not file) + (loop rest system file (cons spec specs)) + (values #f #f))) + ((('load . ('package candidate)) . rest) + (if (and (not file) (null? specs)) + (loop rest system candidate specs) + (values #f #f))) + ((('manifest . candidate) . rest) + (if (and (not file) (null? specs)) + (loop rest system candidate specs) + (values #f #f))) + ((('expression . _) . _) + ;; Arbitrary expressions might be non-deterministic or otherwise depend + ;; on external state so do not cache when they're used. + (values #f #f)) + ((((? transformation-option-key?) . _) . _) + ;; Transformation options are potentially "non-deterministic", or at + ;; least depending on external state (with-source, with-commit, etc.), + ;; so do not cache anything when they're used. + (values #f #f)) + ((('system . system) . rest) + (loop rest system file specs)) + ((_ . rest) (loop rest system file specs))))) ;;; diff --git a/guix/transformations.scm b/guix/transformations.scm index c43c00cdd3..0976f0d824 100644 --- a/guix/transformations.scm +++ b/guix/transformations.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2016, 2017, 2018, 2019, 2020, 2021 Ludovic Courtès <ludo@gnu.org> +;;; Copyright © 2016-2022 Ludovic Courtès <ludo@gnu.org> ;;; Copyright © 2021 Marius Bakke <marius@gnu.org> ;;; ;;; This file is part of GNU Guix. @@ -56,6 +56,7 @@ tuned-package show-transformation-options-help + transformation-option-key? %transformation-options)) ;;; Commentary: @@ -796,6 +797,12 @@ are replaced by their latest upstream version." (and (eq? k key) proc))) %transformations)) +(define (transformation-option-key? key) + "Return true if KEY is an option key (as returned while parsing options with +%TRANSFORMATION-OPTIONS) corresponding to a package transformation option. +For example, (transformation-option-key? 'with-input) => #t." + (->bool (transformation-procedure key))) + ;;; ;;; Command-line handling. |