Subject: [PATCH 0/4] Memoize inferior package access.
From: Ricardo Wurmus <[email-masked]>
To: [email-masked]
Date: Mon, 25 Jan 2021 14:33:59 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Hi Guix,

this patch set improves performance of inferior lookups by caching previous
results.  The change in inferior-package->manifest-entry has the biggest
impact in my test case, where I'm building a profile consisting of a few R
packages.  Without this patch it takes more than 14 seconds.  With cached
results it takes less than a second.

Included is a patch that Ludo provided on #guix-hpc for which I wrote a
commit message.

The test case is attached.

Ludovic Courtès (1):
  inferior: Memoize package input field access.

Ricardo Wurmus (3):
  guix: Fix typo.
  inferior: Memoize inferior-package->manifest-entry.
  inferior: Memoize inferior package search path access.

 guix/inferior.scm | 155 ++++++++++++++++++++++++----------------------
 1 file changed, 81 insertions(+), 74 deletions(-)

base-commit: 90a6ce0b1852608185e3ba7fe09e585b43eac3be
-- 
2.29.2

-- 
Ricardo

(import (guix packages)
        (guix inferior)
        (guix store)
        (guix monads)(guix gexp)
        (guix profiles)
        (guix derivations)
        (ice-9 match)
        (srfi srfi-19))

(pk 'current-guix)
(define current-guix
  ;; /home/rekado/.config/guix/current
  (let* ((default-guix "/gnu/store/ig6alp71w39bmfy51f1w32z0k2rbh6ra-profile")
         (current-guix-inferior #false))
    (lambda ()
      (or current-guix-inferior
          (begin
            (set! current-guix-inferior (open-inferior
                                         (canonicalize-path default-guix)))
            current-guix-inferior)))))

(define (lookup-package specification)
  (match (lookup-inferior-packages (current-guix) specification)
    ((first . rest) first)
    (x (error "oops" x))))

(define specs
  (list "bash-minimal"
        "r-minimal"
        "r-ggplot2"
        "r-ggrepel"
        "r-deseq2"
        "r-dt"
        "r-pheatmap"
        "r-corrplot"
        "r-reshape2"
        "r-plotly"
        "r-scales"
        "r-crosstalk"
        "r-gprofiler"
        "r-rtracklayer"
        "r-summarizedexperiment"))

(pk 'packages)
(define packages
  (map lookup-package specs))

(pk 'packages->manifest)
(let ((start (current-time)))
  (let ((manifest (packages->manifest packages)))
    (pk 'packages->manifest-done (time-difference (current-time) start))))