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<div class="moz-cite-prefix">On 10/3/25 11:32 AM, Charles Oliver
Nutter wrote:<br>
</div>
<blockquote type="cite" cite="mid:CAE-f1xT1vHXNETtuhRVQ-nmX1DGDUQTvrEasUY9D62oyP1wbxQ@mail.gmail.com">
<div dir="ltr">
<div>Thank you for the help, Ioi! A couple questions below.</div>
<div dir="ltr"><br>
</div>
<div dir="ltr">On Thu, Oct 2, 2025 at 5:44 PM <<a href="mailto:ioi.lam@oracle.com" moz-do-not-send="true" class="moz-txt-link-freetext">ioi.lam@oracle.com</a>>
wrote:</div>
<div class="gmail_quote gmail_quote_container">
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div>
<p>However, in JDK 25, we changed the logging of these
messages so they are now printed in the "error" channel.
This is a bug. I have created <a href="https://bugs.openjdk.org/browse/JDK-8369079" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">https://bugs.openjdk.org/browse/JDK-8369079</a> and
will try to backport the fix to JDK 25u.</p>
</div>
</blockquote>
<div>So it's working, but the error output should not be there
and that's what you'll fix? </div>
</div>
</div>
</blockquote>
<p>Yes. In JDK 25 we changed the way for reporting mismatches
between the CDS archive/AOT cache and the actual command-line.
It's probably a bit excessive. I am thinking of changing these
back to the "info" level, so for people who are doing performance
tuning can explicitly enable the log to see what's going on, but
otherwise we won't annoy or scare people.</p>
<br>
<blockquote type="cite" cite="mid:CAE-f1xT1vHXNETtuhRVQ-nmX1DGDUQTvrEasUY9D62oyP1wbxQ@mail.gmail.com">
<div dir="ltr">
<div class="gmail_quote gmail_quote_container">
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div>
<p>Meanwhile, you can add -Xlog:cds=none to disable these
logs.</p>
</div>
</blockquote>
<div>We do that currently so that we can quietly generate the
AppCDS jsa on the first execution of JRuby and use it for
every invocation after that.</div>
<div><br>
</div>
<div>After determining the JDK version by reading in the
"release" file, we choose the best flags to use and add them
to the JRuby "java" command line automatically here:</div>
<div><br>
</div>
<div><a href="https://urldefense.com/v3/__https://github.com/jruby/jruby/blob/master/bin/jruby.sh*L870__;Iw!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXEcPRSae0$" moz-do-not-send="true">https://github.com/jruby/jruby/blob/master/bin/jruby.sh#L870</a></div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div>
<p>A better alternative would be to use the AOT cache. It
will have faster start-up time, and it will store
an archived module graph that matches your command-line
settings.</p>
</div>
</blockquote>
<div>That's the plan! We just have to build support for
AOTCache into our launcher. The fact that a training run
must be done separately requires a bit more work on our end
than just using the AutoCreateSharedArchive (we'll need to
detect if the AOTCache file has been created and adjust the
command line accordingly).</div>
<div><br>
</div>
<div>It will happen, though, and hopefully we'll be able to
quietly AOT on first invocation of JRuby and use that AOT
for future calls without users doing anything special.</div>
</div>
</div>
<br>
</blockquote>
<br>
<p>Please let us know what you come up with. We are interesting in
learning how people use AOT so that we can improve the workflow.</p>
<p>Thanks</p>
<p>- Ioi</p>
<p><br>
</p>
<blockquote type="cite" cite="mid:CAE-f1xT1vHXNETtuhRVQ-nmX1DGDUQTvrEasUY9D62oyP1wbxQ@mail.gmail.com">
<div class="gmail_quote gmail_quote_container">
<div dir="ltr" class="gmail_attr">On Thu, Oct 2, 2025 at 5:48 PM
<<a href="mailto:ioi.lam@oracle.com" moz-do-not-send="true" class="moz-txt-link-freetext">ioi.lam@oracle.com</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div>
<p>Hi Charlie, </p>
<p><br>
</p>
<p> </p>
<blockquote type="cite">[] jdk25 $ rm
/Users/headius/work/jruby/lib/jruby-java25.jsa<br>
[] jdk25 $
/Library/Java/JavaVirtualMachines/zulu-25.jdk/Contents/Home/bin/java
@/Users/headius/work/jruby/bin/.jruby.java_opts
@/Users/headius/work/jruby/bin/.jruby.module_opts
-Xss2048k
-Djffi.boot.library.path=/Users/headius/work/jruby/lib/jni
-Djava.security.egd=<a moz-do-not-send="true">file:/dev/urandom</a>
-XX:+AutoCreateSharedArchive
-XX:SharedArchiveFile=/Users/headius/work/jruby/lib/jruby-java25.jsa
--enable-native-access=org.jruby.dist
--sun-misc-unsafe-memory-access=allow --module-path
/Users/headius/work/jruby/lib/jruby.jar -classpath :
-Djruby.home=/Users/headius/work/jruby
-Djruby.lib=/Users/headius/work/jruby/lib
-Djruby.script=jruby -Djruby.shell=/bin/sh org.jruby.Main
-e 1</blockquote>
<br>
<p>The problem here is -XX:+AutoCreateSharedArchive is for
creating a dynamic CDS archive, which runs on top of the
static CDS archive that comes with the JDK.</p>
<p>The archived module graph is created only for the static
CDS archive (or JEP 483 AOT cache). It's not created for
the dynamic CDS archive. This is because the archived
module graph requires the archiving of Java heap objects,
which is not supported by the dynamic archive.</p>
<p>The errors you saw basically meant that because different
parameters were given for --module-path,
--enable-native-access, etc, than those used when we
created the default CDS archive, we are not able to use
the archived module graph.</p>
<p>This is a performance regression from JDK 24, as the
archived module graph would have also been disabled with
JDK 24.</p>
<p>However, in JDK 25, we changed the logging of these
messages so they are now printed in the "error" channel.
This is a bug. I have created <a href="https://bugs.openjdk.org/browse/JDK-8369079" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">https://bugs.openjdk.org/browse/JDK-8369079</a>
and will try to backport the fix to JDK 25u.</p>
<p>Meanwhile, you can add -Xlog:cds=none to disable these
logs.</p>
<p>A better alternative would be to use the AOT cache. It
will have faster start-up time, and it will store
an archived module graph that matches your command-line
settings.</p>
<p><br>
</p>
<p>Thanks</p>
<p>- Ioi</p>
<p><br>
</p>
<div>On 10/2/25 10:09 AM, Charles Oliver Nutter wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">Full output as a gist: <a href="https://urldefense.com/v3/__https://gist.github.com/headius/88d91118ef1487b4fbff357fecf06904__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXEpThAhgU$" target="_blank" moz-do-not-send="true">https://gist.github.com/headius/88d91118ef1487b4fbff357fecf06904</a></div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Thu, Oct 2, 2025 at
12:03 PM Charles Oliver Nutter <<a href="mailto:headius@headius.com" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">headius@headius.com</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr">Here's the full -Xlog:aot,cds output.
Nothing jumps out at me. It seems to be confused
about which modules are specified at dump time, even
though the same command line sees those modules at
runtime.
<div><br>
</div>
<div>[0.010s][info][cds] trying to map
/Library/Java/JavaVirtualMachines/zulu-25.jdk/Contents/Home/lib/server/classes.jsa<br>
[0.010s][info][cds] Opened shared archive file
/Library/Java/JavaVirtualMachines/zulu-25.jdk/Contents/Home/lib/server/classes.jsa.<br>
[0.010s][info][cds] The shared archive file was
created with UseCompressedOops = 1,
UseCompressedClassPointers = 1,
UseCompactObjectHeaders = 0<br>
[0.010s][info][cds] Core region alignment: 16384<br>
[0.010s][info][cds] trying to map
/Users/headius/work/jruby/lib/jruby-java25.jsa<br>
[0.010s][info][cds] Opened shared archive file
/Users/headius/work/jruby/lib/jruby-java25.jsa.<br>
[0.010s][info][cds] The shared archive file was
created with UseCompressedOops = 1,
UseCompressedClassPointers = 1,
UseCompactObjectHeaders = 0<br>
[0.010s][info][cds] optimized module handling:
disabled because archive was created without
optimized module handling<br>
[0.010s][info][cds] ArchiveRelocationMode: 1<br>
[0.010s][info][cds] ArchiveRelocationMode == 1:
always map archive(s) at an alternative address<br>
[0.010s][info][cds] Try to map archive(s) at an
alternative address<br>
[0.010s][info][cds] Reserved archive_space_rs
[0x0000000f00000000 - 0x0000000f03000000]
(50331648) bytes (includes protection zone)<br>
[0.010s][info][cds] Reserved class_space_rs
[0x0000000f03000000 - 0x0000000f43000000]
(1073741824) bytes<br>
[0.010s][info][cds] Mapped static region #0 at
base 0x0000000f00004000 top 0x0000000f004b0000
(ReadWrite)<br>
[0.010s][info][cds] Mapped static region #1 at
base 0x0000000f004b0000 top 0x0000000f00d94000
(ReadOnly)<br>
[0.010s][info][cds] Mapped static region #2 at
base 0x00000001009d8000 top 0x0000000100a0c000
(Bitmap)<br>
[0.020s][error][cds] An error has occurred while
processing the shared archive file. Run with
-Xlog:aot,cds for details.<br>
[0.020s][error][cds] optimized module handling:
disabled because extra module path(s) are
specified<br>
[0.020s][info ][cds] archived module property
jdk.module.main: (null)<br>
[0.020s][info ][cds] archived module property
jdk.module.addexports: (null)<br>
[0.020s][info ][cds] archived module property
jdk.module.addmods: (null)<br>
[0.020s][info ][cds] archived module property
jdk.module.enable.native.access: (null)<br>
[0.020s][error][cds] Mismatched values for
property jdk.module.enable.native.access:
org.jruby.dist specified during runtime but not
during dump time<br>
[0.020s][error][cds] Disabling optimized module
handling<br>
[0.020s][info ][cds] archived module property
jdk.module.addopens: (null)<br>
[0.020s][error][cds] Mismatched values for
property jdk.module.addopens: java.base/<a href="https://urldefense.com/v3/__http://java.io__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXEjDE2w64$" target="_blank" moz-do-not-send="true">java.io</a>=org.jruby.dist,java.base/java.nio.channels=org.jruby.dist,java.base/<a href="https://urldefense.com/v3/__http://sun.nio.ch__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXELcCRXEk$" target="_blank" moz-do-not-send="true">sun.nio.ch</a>=org.jruby.dist,java.management/sun.management=org.jruby.dist
specified during runtime but not during dump time<br>
[0.020s][error][cds] Disabling optimized module
handling<br>
[0.020s][info ][cds] archived module property
jdk.module.addreads: (null)<br>
[0.020s][info ][cds] optimized module handling:
disabled<br>
[0.020s][info ][cds] full module graph: disabled<br>
[0.021s][info ][cds] Mapped dynamic region #0 at
base 0x0000000f00d94000 top 0x0000000f01a80000
(ReadWrite)<br>
[0.021s][info ][cds] Mapped dynamic region #1 at
base 0x0000000f01a80000 top 0x0000000f02b4c000
(ReadOnly)<br>
[0.021s][info ][cds] Mapped dynamic region #2 at
base 0x0000000101a8c000 top 0x0000000101afc000
(Bitmap)<br>
[0.025s][info ][cds] CDS archive was created with
max heap size = 128M, and the following
configuration:<br>
[0.025s][info ][cds] narrow_klass_base at
mapping start address, narrow_klass_pointer_bits =
32, narrow_klass_shift = 0<br>
[0.025s][info ][cds] narrow_oop_mode = 1,
narrow_oop_base = 0x0000000000000000,
narrow_oop_shift = 3<br>
[0.025s][info ][cds] The current max heap size =
6144M, G1HeapRegion::GrainBytes = 4194304<br>
[0.025s][info ][cds] narrow_klass_base =
0x0000000f00000000, arrow_klass_pointer_bits = 32,
narrow_klass_shift = 0<br>
[0.025s][info ][cds] narrow_oop_mode = 1,
narrow_oop_base = 0x0000000000000000,
narrow_oop_shift = 3<br>
[0.025s][info ][cds] heap range =
[0x0000000680000000 - 0x0000000800000000]<br>
[0.025s][info ][cds] Preferred address to map heap
data (to avoid relocation) is 0x00000007ffe00000<br>
[0.025s][info ][cds] Heap data mapped at
0x00000007ffc00000, size = 1177848 bytes<br>
[0.025s][info ][cds] CDS heap data relocation
delta = -2097152 bytes<br>
[0.025s][info ][aot] initial optimized module
handling: disabled<br>
[0.025s][info ][aot] initial full module graph:
disabled<br>
[0.025s][info ][aot] patching heap embedded
pointers: narrowOop 0xfffc0000 -> 0xfff80000<br>
[0.025s][info ][aot] heap data relocation quick
delta = 0xfffc0000<br>
[0.027s][info ][cds] Unmapping region #2 at base
0x00000001009d8000 (Bitmap)<br>
[0.027s][info ][cds] Unmapping region #2 at base
0x0000000101a8c000 (Bitmap)<br>
[0.027s][info ][aot] Using AOT-linked classes:
false (static archive: no aot-linked classes,
dynamic archive: no aot-linked classes)<br>
</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">On Thu, Oct 2,
2025 at 11:58 AM Charles Oliver Nutter <<a href="mailto:headius@headius.com" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">headius@headius.com</a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<div dir="ltr">
<div>Hello friends!</div>
<div><br>
</div>
<div>I was doing some testing of AppCDS on JDK
25, in hopes of having our Docker images
pre-generate an AppCDS archive. But I
discovered an issue... AppCDS does not appear
to like the JRuby command line anymore in JDK
25.</div>
<div><br>
</div>
<div>Here's part of a session where I delete the
old AppCDS archive and then run the same
command line twice
with AutoCreateSharedArchive. The archive
generates ok in the first command, but then is
rejected by the second command:</div>
<div><br>
</div>
<div>[] jdk25 $ rm
/Users/headius/work/jruby/lib/jruby-java25.jsa<br>
[] jdk25 $
/Library/Java/JavaVirtualMachines/zulu-25.jdk/Contents/Home/bin/java
@/Users/headius/work/jruby/bin/.jruby.java_opts
@/Users/headius/work/jruby/bin/.jruby.module_opts
-Xss2048k
-Djffi.boot.library.path=/Users/headius/work/jruby/lib/jni
-Djava.security.egd=<a moz-do-not-send="true">file:/dev/urandom</a>
-XX:+AutoCreateSharedArchive
-XX:SharedArchiveFile=/Users/headius/work/jruby/lib/jruby-java25.jsa
--enable-native-access=org.jruby.dist
--sun-misc-unsafe-memory-access=allow
--module-path
/Users/headius/work/jruby/lib/jruby.jar
-classpath :
-Djruby.home=/Users/headius/work/jruby
-Djruby.lib=/Users/headius/work/jruby/lib
-Djruby.script=jruby -Djruby.shell=/bin/sh
org.jruby.Main -e 1<br>
[1.074s][warning][cds] Skipping
jdk/proxy2/$Proxy13: Unsupported location<br>
[1.074s][warning][cds] Skipping
jdk/proxy2/$Proxy25: Unsupported location<br>
[1.074s][warning][cds] Skipping
org/joda/time/field/MillisDurationField: Old
class has been linked</div>
<div>...<br>
[1.076s][warning][cds] Skipping
org/jruby/org/objectweb/asm/ClassWriter: Old
class has been linked<br>
[1.076s][warning][cds] Skipping
org/joda/time/format/DateTimeFormatterBuilder$PaddedNumber:
Old class has been linked<br>
[] jdk25 $
/Library/Java/JavaVirtualMachines/zulu-25.jdk/Contents/Home/bin/java
@/Users/headius/work/jruby/bin/.jruby.java_opts
@/Users/headius/work/jruby/bin/.jruby.module_opts
-Xss2048k
-Djffi.boot.library.path=/Users/headius/work/jruby/lib/jni
-Djava.security.egd=<a moz-do-not-send="true">file:/dev/urandom</a>
-XX:+AutoCreateSharedArchive
-XX:SharedArchiveFile=/Users/headius/work/jruby/lib/jruby-java25.jsa
--enable-native-access=org.jruby.dist
--sun-misc-unsafe-memory-access=allow
--module-path
/Users/headius/work/jruby/lib/jruby.jar
-classpath :
-Djruby.home=/Users/headius/work/jruby
-Djruby.lib=/Users/headius/work/jruby/lib
-Djruby.script=jruby -Djruby.shell=/bin/sh
org.jruby.Main -e 1<br>
[0.008s][error][cds] An error has occurred
while processing the shared archive file. Run
with -Xlog:aot,cds for details.<br>
[0.008s][error][cds] optimized module
handling: disabled because extra module
path(s) are specified<br>
[0.008s][error][cds] Mismatched values for
property jdk.module.enable.native.access:
org.jruby.dist specified during runtime but
not during dump time<br>
[0.008s][error][cds] Disabling optimized
module handling<br>
[0.008s][error][cds] Mismatched values for
property jdk.module.addopens: java.base/<a href="https://urldefense.com/v3/__http://java.io__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXEjDE2w64$" target="_blank" moz-do-not-send="true">java.io</a>=org.jruby.dist,java.base/java.nio.channels=org.jruby.dist,java.base/<a href="https://urldefense.com/v3/__http://sun.nio.ch__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXELcCRXEk$" target="_blank" moz-do-not-send="true">sun.nio.ch</a>=org.jruby.dist,java.management/sun.management=org.jruby.dist
specified during runtime but not during dump
time<br>
[0.008s][error][cds] Disabling optimized
module handling<br>
</div>
<div><br>
</div>
<div>The errors make no sense because I'm doing
exactly the same thing in both command lines.</div>
<div><br>
</div>
<div>Here's the contents of the
/Users/headius/work/jruby/bin/.jruby.module_opts
file (the .jruby.java_opts file is empty):</div>
<div><br>
</div>
<div>--add-opens java.base/<a href="https://urldefense.com/v3/__http://java.io__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXEjDE2w64$" target="_blank" moz-do-not-send="true">java.io</a>=org.jruby.dist<br>
--add-opens
java.base/java.nio.channels=org.jruby.dist<br>
--add-opens java.base/<a href="https://urldefense.com/v3/__http://sun.nio.ch__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXELcCRXEk$" target="_blank" moz-do-not-send="true">sun.nio.ch</a>=org.jruby.dist<br>
--add-opens
java.management/sun.management=org.jruby.dist</div>
<div><br>
</div>
<div>Running the same commands against JDK 21
works just fine... the jsa file is generated
and used correctly. Is there something I'm
doing wrong with this command line that JDK 25
does not like?</div>
<div><br>
</div>
<div>I can re-test with another JDK if
necessary. Let me know if I should open a bug
for this.</div>
<div><br>
</div>
<div>Reproduce by downloading JRuby from <a href="https://urldefense.com/v3/__https://jruby.org__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXEZJX495k$" target="_blank" moz-do-not-send="true">https://jruby.org</a>
and unpacking. It runs out of the box.</div>
<div><br>
</div>
<div>
<div dir="ltr" class="gmail_signature">
<div dir="ltr"><b>Charles Oliver Nutter</b>
<div><i>Architect and Technologist</i></div>
<div>Headius Enterprises</div>
<a href="https://urldefense.com/v3/__https://www.headius.com__;!!ACWV5N9M2RV99hQ!LOwPq6NDkMfUvHJpbAvdCCKZZS_Xmb2zVl1dfHvFp9JilpZoE1gEPghExsxAcqYKs7g6xVXETztFUBg$" target="_blank" moz-do-not-send="true">https://www.headius.com</a>
<div>
<div><a href="mailto:headius@headius.com" target="_blank" moz-do-not-send="true" class="moz-txt-link-freetext">headius@headius.com</a></div>
</div>
</div>
</div>
</div>
</div>
</blockquote>
</div>
</blockquote>
</div>
</blockquote>
</div>
</blockquote>
</div>
</blockquote>
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