Help, My Java Object Vanished (and the GC Is Not at Fault)

76 points by todsacerdoti 8 days ago | 8 comments

ErikCorry 7 days ago |
Nice!
Why malloc? Surely this is an on-heap object, not malloc allocated?
tialaramex 4 days ago |
I think you've got yourself confused. The heap is what malloc is allocating. So it's like you said "Surely this is somewhere in Europe, not France?" or "Surely this is a round shape, not a circle?"
comex 4 days ago |
Not when we’re talking about a JVM, which has its own heap that does not use malloc.
tialaramex 4 days ago |
The JVM is of course just software. In this case it's mostly software written in C++ and that software allocates "its own heap" using uh... malloc
https://github.com/openjdk/jdk/blob/master/src/hotspot/share...
pjmlp a day ago |
In the specific case of the OpenJDK, there isn't the one JVM, rather a standard[0], like in ISO languages, with a reference implementation to go along it,
https://en.wikipedia.org/wiki/List_of_Java_virtual_machines
And the list doesn't include all, e.g. PTC (https://www.ptc.com/en/products/developer-tools/perc)
[0] - https://docs.oracle.com/javase/specs/index.html
1718627440 16 hours ago |
malloc is also not a specific implementation, but a standardized interface for allocating on the heap.
cluckindan 4 days ago |
Check your code block CSS, the font sizes are all over the place on mobile (iOS).
By ”you” I mean anyone who has a blog and uses code blocks.
mands 4 days ago |
Great read, both in terms of content, but also the approach to diagnosing the issue and debugging in general.