Replace synchronized blocks with a ReentrantLock. The synchronized bl… #93
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…ocks were removed and replaced by lock.lock() and lock.unlock(). This avoids that the carrier thread (OS thread) is pinned when running on virtual threads which were introduced as a preview feature in JDK 19. The code inside the replaced synchronized blocks in ConnectionImpl and ServerPreparedQuery performed IO, the ones in NativeSession didn't, but were replaced because ServerPreparedQuery synchronized on NativeSession objects. https://openjdk.org/jeps/425 `There are two scenarios in which a virtual thread cannot be unmounted during blocking operations because it is pinned to its carrier: When it executes code inside a synchronized block or method, or When it executes a native method or a foreign function.` See also https://bugs.mysql.com/bug.php?id=109346
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Does this mean it now vanishes into a black hole? Or.... |
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Superseded by #95. |
This is an addition to PR #91 of @bdeneuter:
The code inside the replaced synchronized blocks in ConnectionImpl and ServerPreparedQuery performed IO, the ones in NativeSession didn't, but were replaced because ServerPreparedQuery synchronized on NativeSession objects.
The synchronized blocks were removed and replaced by lock.lock() and lock.unlock(). This avoids that the carrier thread (OS thread) is pinned when running on virtual threads which were introduced as a preview feature in JDK 19.
https://openjdk.org/jeps/425
`There are two scenarios in which a virtual thread cannot be unmounted during blocking operations because it is pinned to its carrier:
When it executes code inside a synchronized block or method, or When it executes a native method or a foreign function.`
See also https://bugs.mysql.com/bug.php?id=109346