On 6/20/24 01:01, Sanne Grinovero wrote:
Hi all,
I was hoping to build a custom JVM which would only have G1GC as a
garbage collector, for some experiments.
Essentially I'm running:
bash configure --with-jvm-variants=custom
--with-jvm-features=cds,compiler1,compiler2,g1gc,jfr,jni-check,jvmci,jvmti,management,services,link-time-opt
--enable-generate-classlist --disable-manpages --with-vendor-name=Experiments
However then during the "make images" step, this will fail when the
jmod(s) are being created, with a long sequence of errors such as:
Creating java.security.jgss.jmod
Error occurred during initialization of VM
Option -XX:+UseSerialGC not supported
The same build succeeds if I add the "serialgc" in the list of
selected features.
Should I open a bug report?
I've verified that both the `master` branch and `jdk23` are affected,
and so is the `premain` branch on the Leyden fork.
Yes, I think that may be warranted, however see workaround below.
I'm assuming that it should be supported to build a JVM without the
serialgc implementation since it's listed as a feature and therefore
I'd expect it to be OK to disable it, however I'm wondering about this
explicitly stated need during the jmod building process; is there
perhaps a specific need for these to be built with the serialgc, or is
this just a hint meant to make the build more efficient?
There is no specific need, this is just for efficiency. Using the
"small" java configuration, saves considerable user time for small short
lived java processes. We currently don't take any limitations in the
configuration for the built JDK into account when using it as the
"BUILD_JDK" during the build. Perhaps we should. On the other hand, if
you are building a limited JDK through configuration options, it can
often be adviceable to supply a separate BUILD_JDK (for performing the
build steps that need a JDK N). This can be done by first building a
standard configuration and then pointing to that JDK image with the
configure arg --with-build-jdk.
/Erik
Many thanks,
Sanne Grinovero
