Major Clojure 1.10 performance degredation on JDK11

Elana Hashman ehashman at
Sun Feb 10 16:12:29 GMT 2019

On Sun, Feb 10, 2019 at 02:30:16AM -0600, Rob Browning wrote:
> Offhand I'd guess that either there's just some new issue, or perhaps
> there are jars that were built with the older version of
> dh_strip_notdeterminism lingering and getting in the way somehow.

I think this is the case:

time java -cp debian/libclojure-java/usr/share/java/clojure-1.10.0.jar clojure.main -e ''

real	0m4.409s
user	0m14.051s
sys	0m0.366s
time java -cp debian/libclojure-java/usr/share/java/clojure-1.10.0.jar clojure.main -e ''

real	0m13.885s
user	0m33.468s
sys	0m0.704s

I'm gonna guess, based on my earlier testing, that other 4s of startup
time can be accounted for by the fact that spec and core.specs are built
with stripped nondeterminism. Let me try turning that off in a -2
release and see if that solves the other ~3s of slowness.

> For what it's worth, I think the fix did something to make it so that
> the class timestamps would be at least a second newer than the clj
> timestamps (while still deterministic), and if I recall correctly, Chris
> Lamb came up with the fix.

cc'd, because this seems to be back, and I'm not sure if we should
reopen the bug or do something else here.

- e
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <>

More information about the Pkg-clojure-maintainers mailing list