To expand on Michael’s comment. static simply means not associated with an instance of the containing class. volatile simply means that the value may be changed by other threads without warning. So your question boils down to “can a field not associated with an instance of the containing class be changed by another thread without … Read more
Solution to this problem was to upgrade docker from version 18.06.1-ce to 20.10.7. Why? This is because the default seccomp profile of Docker 20.10.9 is not adjusted to support the clone() syscall wrapper of glibc 2.34 adopted in Ubuntu 21.10 and Fedora 35. Source: ubuntu:21.10 and fedora:35 do not work on the latest Docker (20.10.9)
I tried something, and it seems to work. I put preload_app = True in my gunicorn.conf and now the lock seems to be shared. I am still looking into exactly what’s happening here but for now this is good enough, YMMV.
If you want concurrency, here’s a very simple example: from multiprocessing import Process def loop_a(): while 1: print(“a”) def loop_b(): while 1: print(“b”) if __name__ == ‘__main__’: Process(target=loop_a).start() Process(target=loop_b).start() This is just the most basic example I could think of. Be sure to read http://docs.python.org/library/multiprocessing.html to understand what’s happening. If you want to send data … Read more
As far as I can tell, TimeoutError is actually raised when you would expect it, and not after the task is finished. However, your program itself will keep on running until all running tasks have been completed. This is because currently executing tasks (in your case, probably all your submitted tasks, as your pool size … Read more
So I’ve run the experiment and the Rhino engine reports “Mozilla Rhino” is MULTITHREADED which the JavaDocs asserts “MULTITHREADED” – The engine implementation is internally thread-safe and scripts may execute concurrently although effects of script execution on one thread may be visible to scripts on other threads.” Here’s the code…it looks threadsafe to me, as … Read more
While you will not get an invalid state by changing arrays as you mention, you will have the same problem that happens when two threads are viewing a non volatile integer without synchronization (see the section in the Java Tutorial on Memory Consistency Errors). Basically, the problem is that Thread 1 may write a value … Read more
The end of a constructor is a special place in terms of concurrency, with respect to final fields. From section 17.5 of the Java Language Specification: An object is considered to be completely initialized when its constructor finishes. A thread that can only see a reference to an object after that object has been completely … Read more
You link is for the HashMap in Java 6. It was rewritten in Java 8. Prior to this rewrite an infinite loop on get(Object) was possible if there were two writing threads. I am not aware of a way the infinite loop on get can occur with a single writer. Specifically, the infinite loop occurs … Read more