4 ms·

> We were in the early phases of forking the JVM definitely made me go :-O - how big a company do you need to be for that to be a realistic thing to maintain i

by zem 1y ago

> We were in the early phases of forking the JVM definitely made me go :-O - how big a company do you need to be for that to be a realistic thing to maintain in house?

dcrazy 1y ago
You don’t need to be big, you just need to handle lots of money.
- zem 1y ago
  fair point, I guess this was a high frequency trading firm or similar, who could justify paying a few engineers to maintain a jvm fork
cbzoiav 1y ago
A fork can be many things. I've maintained in house forks of major code bases with a handful of minor code changes while we've tried to convince upstream to accept them.
scheme271 1y ago
Off-hand I think that there were at least 7 forks/implementations out there. Oracle/Sun, Oracle's Graal, IBM, OpenJDK, Amazon Coretto, Twitter's fork, and Azul. There's also a GNU effort but I don't think that really went very far. I think there's probably a few others that aren't publicly well known for trading firms, etc.
- brabel 1y ago
  > there were at least 7 forks/implementations out there There are 17 listed on SDKMAN's website: https://sdkman.io/jdks https://sdkman.io/jdks > OpenJDK As far as I know, all other distributions of the JDK are forks of OpenJDK. Would love to know if there's any that isn't.
  - pjmlp 1y ago
    Commercial embedded vendors with RTOS capabilities, https://www.ptc.com/en/products/developer-tools/perc https://www.ptc.com/en/products/developer-tools/perc https://www.aicas.com/products-services/jamaicavm/ https://www.aicas.com/products-services/jamaicavm/ JikesRVM (https://www.jikesrvm.org https://www.jikesrvm.org) no longer active, but it was its own thing. Then you have Azul Zing and OpenJ9, which use parts of OpenJDK for the standard library part, but the foundations are their own thing. https://www.azul.com/products/prime/ https://www.azul.com/products/prime/ https://developer.ibm.com/components/open-j9/ https://developer.ibm.com/components/open-j9/ Then you have that mobile OS, which isn't really JVM compliant implementation, but it is close enough for many workloads and libraries to work on top of it.
- _glass 1y ago
  SAP has also a fork: https://github.com/SAP/SapMachine https://github.com/SAP/SapMachine.
- throwaway2037 1y ago
  JetBrains also has a fork that they use to run some (all?) of their IDEs, such as CLion (C/C++) and IntelliJ (Java). As I understand, it has many fixes for HiDPI environments when painting GUI widgets (Swing, etc.).

by zem 1y ago

> We were in the early phases of forking the JVM definitely made me go :-O - how big a company do you need to be for that to be a realistic thing to maintain in house?

dcrazy 1y ago

You don’t need to be big, you just need to handle lots of money.

zem 1y ago
fair point, I guess this was a high frequency trading firm or similar, who could justify paying a few engineers to maintain a jvm fork

cbzoiav 1y ago

A fork can be many things. I've maintained in house forks of major code bases with a handful of minor code changes while we've tried to convince upstream to accept them.

scheme271 1y ago

Off-hand I think that there were at least 7 forks/implementations out there. Oracle/Sun, Oracle's Graal, IBM, OpenJDK, Amazon Coretto, Twitter's fork, and Azul. There's also a GNU effort but I don't think that really went very far. I think there's probably a few others that aren't publicly well known for trading firms, etc.

brabel 1y ago
> there were at least 7 forks/implementations out there There are 17 listed on SDKMAN's website: https://sdkman.io/jdks https://sdkman.io/jdks > OpenJDK As far as I know, all other distributions of the JDK are forks of OpenJDK. Would love to know if there's any that isn't.
- pjmlp 1y ago
  Commercial embedded vendors with RTOS capabilities, https://www.ptc.com/en/products/developer-tools/perc https://www.ptc.com/en/products/developer-tools/perc https://www.aicas.com/products-services/jamaicavm/ https://www.aicas.com/products-services/jamaicavm/ JikesRVM (https://www.jikesrvm.org https://www.jikesrvm.org) no longer active, but it was its own thing. Then you have Azul Zing and OpenJ9, which use parts of OpenJDK for the standard library part, but the foundations are their own thing. https://www.azul.com/products/prime/ https://www.azul.com/products/prime/ https://developer.ibm.com/components/open-j9/ https://developer.ibm.com/components/open-j9/ Then you have that mobile OS, which isn't really JVM compliant implementation, but it is close enough for many workloads and libraries to work on top of it.
_glass 1y ago
SAP has also a fork: https://github.com/SAP/SapMachine https://github.com/SAP/SapMachine.
throwaway2037 1y ago
JetBrains also has a fork that they use to run some (all?) of their IDEs, such as CLion (C/C++) and IntelliJ (Java). As I understand, it has many fixes for HiDPI environments when painting GUI widgets (Swing, etc.).