JDK
Graal
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JDK | Graal | |
---|---|---|
191 | 156 | |
18,393 | 19,765 | |
2.4% | 0.9% | |
10.0 | 10.0 | |
1 day ago | 7 days ago | |
Java | Java | |
GNU General Public License v3.0 only | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
JDK
- JEP draft: Exception handling in switch
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Java 23: The New Features Are Officially Announced
Completely gutted from the OpenJDK, last I checked. See here for the culprit PR: https://github.com/openjdk/jdk/pull/18688
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macOS 14.4 might break Java on your machine
> Yes, they're changing one aspect of signal handler use to work around this problem. They're not stopping the use of signal handlers in general. Hotspot continues to use signals for efficiency in general. See https://github.com/openjdk/jdk/blob/9059727df135dc90311bd476...
This whole thread is about SIGSEGV, and specifically their SIGSEGV handling. However, catching normal signals is not about efficiency.
Some of their exception handling is still odd: There is no reason for a program that receives SIGILL to ever attempt continuing. But others is fine, like catching SIGFPE to just forward an exception to the calling code.
(Sure, you could construct an argument to say that this is for efficiency if you considered the alternative to be implementing floating point in software so that all exceptions exist in user-space, but hardware floating point is the norm and such alternative would be wholly unreasonable.)
> The wonderful thing about choosing not to care about facts is having whatever opinions you want.
I appreciate the irony of you making such statement, proudly thinking that your opinion equals fact, and therefore any other opinion is not.
This discussion is nothing but subjective opinion vs. subjective opinion. Facts are (hopefully, as I can only speak for myself) inputs to both our opinions, but no opinion about "good" or "bad", "nasty" or not can ever be objective. Objective code quality does not exist.
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The Return of the Frame Pointers
I remember talking to Brendan about the PreserveFramePointer patch during my first months at Netflix in 2015. As of JDK 21, unfortunately it is no longer a general purpose solution for the JVM, because it prevents a fast path being taken for stack thawing for virtual threads: https://github.com/openjdk/jdk/blob/d32ce65781c1d7815a69ceac...
- JDK-8180450: secondary_super_cache does not scale well
- The One Billion Row Challenge
- AVX2 intrinsics for Arrays.sort methods (int, float arrays)
- A gentle introduction to two's complement
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Java JEP 461: Stream Gatherers
Map doesn't implement the Collection interface.
https://github.com/openjdk/jdk/blob/master/src/java.base/sha...
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C++23: Removing garbage collection support
C++ lets you write anything you can imagine, and the language features and standard library often facilitate that. The committee espouses the view that they want to provide many "zero [runtime] cost," abstractions. Anybody can contribute to the language, although the committee process is often slow and can be political, each release the surface area and capability of the language gets larger.
I believe Hazard Pointers are slated for C++26, and these will add a form "free later, but not quite garbage collection" to the language. There was a talk this year about using hazard pointers to implement a much faster std::shared_ptr.
It's a language with incredible depth because so many different paradigms have been implemented in it, but also has many pitfalls for new and old users because there are many different ways of solving the same problem.
I feel that in C++, more than any other language, you need to know the actual implementation under the hood to use it effectively. This means knowing not just what the language specifies, but can occaissionally require knowing what GCC or Clang generate on your particular hardware.
Many garbage collected languages are written in or have parts of their implementations in C++. See JS (https://github.com/v8/v8)and Java GC (https://github.com/openjdk/jdk/tree/36de19d4622e38b6c00644b0...)
I am not an expert on Java (or C++), so if someone knows better or can add more please correct me.
Graal
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Java 23: The New Features Are Officially Announced
Contrary to what vocal Kotlin advocates might believe, Kotlin only matters on Android, and that is thanks to Google pushing it no matter what.
https://spectrum.ieee.org/the-top-programming-languages-2023
https://snyk.io/reports/jvm-ecosystem-report-2021/
And even so, they had to conceed Android and Kotlin on their own, without the Java ecosystem aren't really much useful, thus ART is now updatable via Play Store, and currently supports OpenJDK 17 LTS on Android 12 and later devices.
As for your question regarding numbers, mostly Java 74.6%, C++ 13.7%, on the OpenJDK, other JVM implementations differ, e.g. GraalVM is mostly Java 91.8%, C 3.6%.
https://github.com/openjdk/jdk
https://github.com/oracle/graal
Two examples from many others, https://en.wikipedia.org/wiki/List_of_Java_virtual_machines
- FLaNK Stack 05 Feb 2024
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Apple releases Pkl – onfiguration as code language
Pkl was built using the GraalVM Truffle framework. So it supports runtime compilation using Futurama Projections. We have been working with Apple on this for a while, and I am quite happy that we can finally read the sources!
https://github.com/oracle/graal/tree/master/truffle
Disclaimer: graalvm dev here.
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Live Objects All the Way Down: Removing the Barriers Between Apps and VMs
That's pretty interesting. It's not as aggressive as Bee sounds, but the Espresso JVM is somewhat similar in concept. It's a full blown JVM written in Java with all the mod cons, which can either be compiled ahead of time down to memory-efficient native code giving something similar to a JVM written in C++, or run itself as a Java application on top of another JVM. In the latter mode it obviously doesn't achieve top-tier performance, but the advantage is you can easily hack on it using all the regular Java tools, including hotswapping using the debugger.
When run like this, the bytecode interpreter, runtime system and JIT compiler are all regular Java that can be debugged, edited, explored in the IDE, recompiled quickly and so on. Only the GC is provided by the host system. If you compile it to native code, the GC is also written in Java (with some special conventions to allow for convenient direct memory access).
What's most interesting is that Espresso isn't a direct translation of what a classical C++ VM would look like. It's built on the Truffle framework, so the code is extremely high level compared to traditional VM code. Details like how exactly transitions between the interpreter/compiled code happen, how you communicate pointer maps to the GC and so on are all abstracted away. You don't even have to invoke the JIT compiler manually, that's done for you too. The only code Espresso really needs is that which defines the semantics of the Java bytecode language and associated tools like the JDWP debugger protocol.
https://github.com/oracle/graal/tree/master/espresso
This design makes it easy to experiment with new VM features that would be too difficult or expensive to implement otherwise. For example it implements full hotswap capability that lets you arbitrarily redefine code and data on the fly. Espresso can also fully self-host recursively without limit, meaning you can achieve something like what's described in the paper by running Espresso on top of Espresso.
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Crash report and loading time
I'm also using GraalVM if that's of any help.
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Quarkus 3.4 - Container-first Java Stack: Install with OpenJDK 21 and Create REST API
Quarkus is one of Java frameworks for microservices development and cloud-native deployment. It is developed as container-first stack and working with GraalVM and HotSpot virtual machines (VM).
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Level-up your Java Debugging Skills with on-demand Debugging
Apologies, I didn't mean to imply DCEVM went poof, just that I was sad it didn't make it into OpenJDK so one need not do JDK silliness between the production one and the "debugging one" since my experience is that's an absolutely stellar way to produce Heisenbugs
And I'll be straight: Graal scares me 'cause Oracle but I just checked and it looks to the casual observer that it's straight-up GPLv2 now so maybe my fears need revisiting: https://github.com/oracle/graal/blob/vm-23.1.0/LICENSE
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Rust vs Go: A Hands-On Comparison
> to be compiled to a single executable is a strength that Java does not have
I think this is very outdated claim: https://www.graalvm.org/
- Leveraging Rust in our high-performance Java database
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Java 21 makes me like Java again
https://github.com/oracle/graal/issues/7182
What are some alternatives?
aircraft - The A32NX & A380X Project are community driven open source projects to create free Airbus aircraft in Microsoft Flight Simulator that are as close to reality as possible.
Liberica JDK - Free and 100% open source Progressive Java Runtime for modern Javaâ„¢ deployments supported by a leading OpenJDK contributor
steam-runtime - A runtime environment for Steam applications
Adopt Open JDK - Eclipse Temurinâ„¢ build scripts - common across all releases/versions
OkHttp - Square’s meticulous HTTP client for the JVM, Android, and GraalVM.
awesome-wasm-runtimes - A list of webassemby runtimes
kitten - A statically typed concatenative systems programming language.
SAP Machine - An OpenJDK release maintained and supported by SAP
intellij-community - IntelliJ IDEA Community Edition & IntelliJ Platform
maven-jpackage-template - Sample project illustrating building nice, small cross-platform JavaFX or Swing desktop apps with native installers while still using the standard Maven dependency system.
imagepipe - Image processing pipeline
wasmer - 🚀 The leading Wasm Runtime supporting WASIX, WASI and Emscripten