From 7cfd789150f448cf5256b88915bae4163cc9db03 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= Date: Thu, 28 Jan 2021 22:48:21 +0100 Subject: inferior: Speed up 'cached-channel-instance' for cache hits. That way a command like: guix time-machine --commit=5aeee07cc9 -- describe goes from 3.4s to 0.5s on a cache hit, even slightly less when passing the full commit ID. * guix/inferior.scm (channel-full-commit): New procedure. (cached-channel-instance): Remove 'instances' top-level variable. Add 'commits' and use it for 'key'. Move 'latest-channel-instances' call to the cache miss case. --- guix/inferior.scm | 38 ++++++++++++++++++++++++++++++-------- 1 file changed, 30 insertions(+), 8 deletions(-) (limited to 'guix') diff --git a/guix/inferior.scm b/guix/inferior.scm index 65d7888669..0990696e6c 100644 --- a/guix/inferior.scm +++ b/guix/inferior.scm @@ -1,5 +1,5 @@ ;;; GNU Guix --- Functional package management for GNU -;;; Copyright © 2018, 2019, 2020 Ludovic Courtès +;;; Copyright © 2018, 2019, 2020, 2021 Ludovic Courtès ;;; ;;; This file is part of GNU Guix. ;;; @@ -40,6 +40,7 @@ #:use-module (guix search-paths) #:use-module (guix profiles) #:use-module (guix channels) + #:use-module ((guix git) #:select (update-cached-checkout)) #:use-module (guix monads) #:use-module (guix store) #:use-module (guix derivations) @@ -51,6 +52,7 @@ #:autoload (guix build utils) (mkdir-p) #:use-module (srfi srfi-1) #:use-module (srfi srfi-26) + #:use-module (srfi srfi-71) #:autoload (ice-9 ftw) (scandir) #:use-module (ice-9 match) #:use-module (ice-9 popen) @@ -691,6 +693,21 @@ failing when GUIX is too old and lacks the 'guix repl' command." (make-parameter (string-append (cache-directory #:ensure? #f) "/inferiors"))) +(define (channel-full-commit channel) + "Return the commit designated by CHANNEL as quickly as possible. If +CHANNEL's 'commit' field is a full SHA1, return it as-is; if it's a SHA1 +prefix, resolve it; and if 'commit' is unset, fetch CHANNEL's branch tip." + (let ((commit (channel-commit channel)) + (branch (channel-branch channel))) + (if (and commit (= (string-length commit) 40)) + commit + (let* ((ref (if commit `(commit . ,commit) `(branch . ,branch))) + (cache commit relation + (update-cached-checkout (channel-url channel) + #:ref ref + #:check-out? #f))) + commit)))) + (define* (cached-channel-instance store channels #:key @@ -701,15 +718,16 @@ failing when GUIX is too old and lacks the 'guix repl' command." The directory is a subdirectory of CACHE-DIRECTORY, where entries can be reclaimed after TTL seconds. This procedure opens a new connection to the build daemon. AUTHENTICATE? determines whether CHANNELS are authenticated." - (define instances - (latest-channel-instances store channels - #:authenticate? authenticate?)) + (define commits + ;; Since computing the instances of CHANNELS is I/O-intensive, use a + ;; cheaper way to get the commit list of CHANNELS. This limits overhead + ;; to the minimum in case of a cache hit. + (map channel-full-commit channels)) (define key (bytevector->base32-string (sha256 - (string->utf8 - (string-concatenate (map channel-instance-commit instances)))))) + (string->utf8 (string-concatenate commits))))) (define cached (string-append cache-directory "/" key)) @@ -737,8 +755,12 @@ determines whether CHANNELS are authenticated." (if (file-exists? cached) cached (run-with-store store - (mlet %store-monad ((profile - (channel-instances->derivation instances))) + (mlet* %store-monad ((instances + -> (latest-channel-instances store channels + #:authenticate? + authenticate?)) + (profile + (channel-instances->derivation instances))) (mbegin %store-monad (show-what-to-build* (list profile)) (built-derivations (list profile)) -- cgit v1.2.3