There is a moment that a thread A writes event data to its thread-local Jfrbuffer, and other thread B flushes the content of the JfrBuffer to file concurrently.

The pos of the JfrBuffer will be updated by the thread A after an event is written done(jfrStorageAdapter.hpp commit),

the thread B will flush the content between the top and pos of the JfrBuffer(jfrStorage.cpp ThreadLocalConcurrentWriteOperation).

The question is how to ensure that the content flushed by the thread B is correct.

There is no release store when the thread A updates the value of pos and no load-acquire when the flush thread read the value of pos.

So it is possible that the thread B reads the new value of pos, but can't read the correct value between the top and pos of the JfrBuffer on hardware having weaker memory models.