Fixes <https://issues.guix.gnu.org/77606>.
Calling ‘fdatasync’ for each and every narinfo file created by ‘guix
substitute’ proved to be too expensive on spinning HDDs and/or under
load (from 0.1s to 1.3s for the ‘fdatasync’ call alone).
* guix/git-authenticate.scm (cache-authenticated-commit): Pass #:sync? #f.
* guix/http-client.scm (http-fetch/cached): Likewise.
* guix/scripts/discover.scm (write-publish-file): Likewise.
* guix/scripts/style.scm (format-whole-file): Likewise.
* guix/substitutes.scm (cache-narinfo!): Likewise.
Reported-by: Christopher Baines <mail@cbaines.net>
Change-Id: I82297eae737bc5aae8a3f7604119e9f3d4b625bf
This was obtained by setting up this environment:
guix shell -D guix --with-input=guile@3.0.9=guile-next \
--with-commit=guile-next=e2ed33ef0445c867fe56c247054aa67e834861f2
-- make -j5
then adding 'unused-module' to (@@ (guix build compiler) %warnings),
building, and checking all the "unused module" warnings and removing
those that were definitely unused.