Hi,
(CC-ing Ludo, who wrote the code according to git logs)
during testing of wip-haskell I observed the make-dynamic-linker-cache
phase is taking alot of time (up to two minutes on a fast machine with
SSD). Looking at ghc-hindent for example [1]:
starting phase `make-dynamic-linker-cache'
created
'/gnu/store/2nrzbaxmqs2rq9yv52bpyn2azb3qj6h1-ghc-hindent-5.3.4/etc/ld.so.cache'
from 10085 library search path entries
phase `make-dynamic-linker-cache' succeeded after 119.5 seconds
And while Haskell packages link to a pretty large number of dynamic
libraries (116 in this case), 10000 search path entries seems wrong. Running
just
(file-needed/recursive
"/gnu/store/2nrzbaxmqs2rq9yv52bpyn2azb3qj6h1-ghc-hindent-5.3.4/bin/hindent")
takes a long time and reveals entries like
/gnu/store/1cyk8j2nd6r0cvm6kx1408kd763yf8h5-ghc-9.2.5/lib/ghc-9.2.5/Cabal-3.6.3.0/../directory-1.3.6.2/../unix-2.7.2.2/../bytestring-0.11.3.1/../template-haskell-2.18.0.0/../pretty-1.1.3.6/../array-0.5.4.0/../base-4.16.4.0/../ghc-bignum-1.2/../ghc-prim-0.8.0/libHSghc-prim-0.8.0-ghc9.2.5.so
so it looks like it deduplicates values, but does not canonicalize
paths. A relatively straight-forward fix could be the following change,
but I don’t know if that would cause any issues, since canonicalize-path
throws an exception if the resulting path does not exist. It’s also
a world rebuild since pretty much any package uses this phase (and the
reason and I cannot test it on a larger scale).
---snip---
diff --git a/guix/build/gremlin.scm b/guix/build/gremlin.scm
index 2a74d51dd9..6eb8f688ea 100644
--- a/guix/build/gremlin.scm
+++ b/guix/build/gremlin.scm
@@ -285,8 +285,8 @@ (define (file-needed/recursive file)
(if (and runpath needed)
(let* ((runpath (map (cute expand-origin <> (dirname file))
runpath))
- (resolved (map (cut search-path runpath <>)
- needed))
+ (resolved (map (lambda (x) (and=> x canonicalize-path))
(map (cut search-path runpath <>)
+ needed)))
(failed (filter-map (lambda (needed resolved)
(and (not resolved)
(not (libc-library?
needed))
---snap---
Cheers,
Lars
[1] https://ci.guix.gnu.org/build/366156/log/raw
