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headius / stringio.diff
Created December 2, 2025 02:52
Removing ptr from StringIO, which is not compatible with dup'ing
diff --git a/ext/java/org/jruby/ext/stringio/StringIO.java b/ext/java/org/jruby/ext/stringio/StringIO.java
index f3ab1cf..9c58077 100644
--- a/ext/java/org/jruby/ext/stringio/StringIO.java
+++ b/ext/java/org/jruby/ext/stringio/StringIO.java
@@ -79,27 +79,17 @@ import static org.jruby.util.RubyStringBuilder.types;
@JRubyClass(name="StringIO")
@SuppressWarnings("serial")
public class StringIO extends RubyObject implements EncodingCapable, DataType {
- static class StringIOData {
- /**
@headius
headius / completely_wrong.java
Last active November 20, 2025 00:39
// This code was generated by AI. It's completely wrong.
public static RubyFixnum newFixnum(Ruby runtime, long value) {
if (value < Byte.MIN_VALUE || value > Byte.MAX_VALUE) {
return newFixnum(runtime, (byte) value);
} else if (value < Short.MIN_VALUE || value > Short.MAX_VALUE) {
return newFixnum(runtime, (short) value);
} else if (value < Integer.MIN_VALUE || value > Integer.MAX_VALUE) {
return newFixnum(runtime, (int) value);
}
@headius
headius / gist:15413f657dad8d83c474114f8f9cf26a
Created November 4, 2025 04:47
fast-ruby benchmarks comparing JRuby 10.0.3.0-head with CRuby 3.4.7
$ ruby -e 'files = Dir["code/**/*.rb"]; files.each_with_index {|file, i| puts "#{i+1}/#{files.size}: #{file}"; system "jruby #{file}"; system "/Users/headius/.rubies/ruby-3.4.7/bin/ruby --jit #{file}" }'
1/68: code/array/array-concat-vs-+.rb
jruby 10.0.3.0-SNAPSHOT (3.4.5) 2025-11-04 d74cb7a2e0 OpenJDK 64-Bit Server VM 21.0.8+9-LTS on 21.0.8+9-LTS +indy +jit [arm64-darwin]
Warming up --------------------------------------
Array#concat 289.000 i/100ms
Array#+ 1.000 i/100ms
Calculating -------------------------------------
Array#concat 3.037k (± 1.1%) i/s (329.29 μs/i) - 15.317k in 5.044432s
Array#+ 13.653 (± 0.0%) i/s (73.24 ms/i) - 69.000 in 5.059999s
@headius
headius / gist:a824c87293ac8f96bfa65f8f838da7cd
Created October 22, 2025 20:33
Single-jar deployment of Sidekiq running the plain-old-Ruby example
sidekiq $ export RAILS_VERSION=7.1
sidekiq $ bundle
...
Bundle complete! 21 Gemfile dependencies, 88 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.
sidekiq $ warble
rm -f sidekiq.jar
Creating sidekiq.jar
sidekiq $ export JDK_JAVA_OPTIONS=-Djava.net.preferIPv4Stack=true
sidekiq $ java -jar sidekiq.jar -r ./examples/por.rb
@headius
headius / console.txt
Created October 17, 2025 18:02
Two steps to create a redistributable Ruby app in an executable jar
[] image_voodoo_demo $ jruby -Ilib exe/voodoo PXL_20250802_162259596.jpg
wrote demo files to /Users/headius/work/image_voodoo_demo/PXL_20250802_162259596/
[] image_voodoo_demo $ ls PXL_20250802_162259596
border.jpg cropped_thumb.jpg cropped.jpg reduced.jpg resized.jpg resized.png thumb.jpg
[] image_voodoo_demo $ rm -rf PXL_20250802_162259596
[] image_voodoo_demo $ gem install warbler
Fetching warbler-2.1.0.gem
Successfully installed warbler-2.1.0
Parsing documentation for warbler-2.1.0
Installing ri documentation for warbler-2.1.0
@headius
headius / gist:88d91118ef1487b4fbff357fecf06904
Created October 2, 2025 17:07
JDK25 failing to load JRuby AppCDS JSA
] jdk25 $ rm /Users/headius/work/jruby/lib/jruby-java25.jsa
[] 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=file:/dev/urandom -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 -Xlog:aot,cds org.jruby.Main -e 1
[0.007s][info][cds] Specified shared archive file not found (/Users/headius/work/jruby/lib/jruby-java25.jsa)
[0.012s][info][cds] trying to map /Library/Java/JavaVirtualMachines/zulu-25.jdk/Contents/Home/lib/server/classes.jsa
[0.012s][info][cds] Opened shared archive file /Librar
@headius
headius / training.md
Last active September 20, 2025 15:52
pre-trained JRuby + AOT for gem list

This is an experiment to pre-train and AOT enough of JRuby to get startup time for "gem list" down to a reasonable speed. I've tried various combintions and so far this seems to be the best, but the timings are highly variable.

Step 1: Perform a gem list while dumping IR. This saves the compiled IR for all loaded files to disk, to skip parsing and compiling in future runs.

jruby --dev -Xir.writing -S gem list > /dev/null

Step 2: Train AOT by running the following script repeatedly with the given JRuby arguments. Requires a small JRuby patch because IR reading breaks for any script has not been written (like the training script).

@headius
headius / gist:cf18f247c1a66f36210b50fcb10304f0
Created May 7, 2025 15:38
JRuby 10 start up and get NMT dump
Native Memory Tracking:
(Omitting categories weighting less than 1KB)
Total: reserved=1341322KB, committed=143578KB
malloc: 30682KB #118112, peak=33492KB #117863
mmap: reserved=1310640KB, committed=112896KB
- Java Heap (reserved=57344KB, committed=32768KB)
(mmap: reserved=57344KB, committed=32768KB, at peak)
@headius
headius / gist:911b66eac8d0cb8ef7b9f2ff8d9f4133
Created March 20, 2025 22:11
Crash loading shared archive on 23+valhalla build
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGBUS (0xa) at pc=0x0000000103e8e604, pid=4379, tid=35331
#
# JRE version: OpenJDK Runtime Environment (23.0+1) (build 23-valhalla+1-90)
# Java VM: OpenJDK 64-Bit Server VM (23-valhalla+1-90, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, bsd-aarch64)
# Problematic frame:
# V [libjvm.dylib+0x9ce604] SystemDictionaryShared::ArchiveInfo::lookup_lambda_proxy_class(LambdaProxyClassKey*)+0x5c
#
@headius
headius / no_eager_singleton.diff
Created March 5, 2025 08:09
diff --git a/core/src/main/java/org/jruby/RubyBasicObject.java b/core/src/main/java/org/jruby/RubyBasicObject.java
index 4edab9b18a..985f2d1911 100644
--- a/core/src/main/java/org/jruby/RubyBasicObject.java
+++ b/core/src/main/java/org/jruby/RubyBasicObject.java
@@ -1791,8 +1791,8 @@ public class RubyBasicObject implements Cloneable, IRubyObject, Serializable, Co
* it possible to emulate both instance_eval and instance_exec
* with this implementation.
*/
- protected IRubyObject yieldUnder(final ThreadContext context, RubyModule under, IRubyObject[] args, Block block, EvalType evalType) {
- context.preExecuteUnder(this, under, block);