From aaa848f3afa81ec79579071f99d9bea5f8456f32 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= Date: Sat, 1 Sep 2012 19:21:06 +0200 Subject: [PATCH] Optimize `write-derivation' and `derivation-path->output-path'. * guix/derivations.scm (write-derivation): Explicitly use `simple-format'. (derivation-path->output-path): Memoize. --- guix/derivations.scm | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/guix/derivations.scm b/guix/derivations.scm index 213d9d5586..c9db580de6 100644 --- a/guix/derivations.scm +++ b/guix/derivations.scm @@ -200,6 +200,10 @@ available in STORE, recursively." "Write the ATerm-like serialization of DRV to PORT. See Section 2.4 of Eelco Dolstra's PhD dissertation for an overview of a previous version of that form." + + ;; Make sure we're using the faster implementation. + (define format simple-format) + (define (list->string lst) (string-append "[" (string-join lst ",") "]")) @@ -269,12 +273,15 @@ that form." (stringoutput-path path #:optional (output "out")) - "Read the derivation from PATH (`/nix/store/xxx.drv'), and return the store +(define derivation-path->output-path + ;; This procedure is called frequently, so memoize it. + (memoize + (lambda* (path #:optional (output "out")) + "Read the derivation from PATH (`/nix/store/xxx.drv'), and return the store path of its output OUTPUT." - (let* ((drv (call-with-input-file path read-derivation)) - (outputs (derivation-outputs drv))) - (and=> (assoc-ref outputs output) derivation-output-path))) + (let* ((drv (call-with-input-file path read-derivation)) + (outputs (derivation-outputs drv))) + (and=> (assoc-ref outputs output) derivation-output-path))))) ;;;