Re: [libvirt-users] is libvirt java binding thread safe?
On Fri, Sep 03, 2010 at 01:02:09PM +0200, Matthias Bolte wrote:
Ah, okay, now I understand what you want to say.
You have two threads A and B. When A runs on its own then it's just
fine, but when you add B (that triggers an exception on purpose and
ignores it) then A picks it up and reports it. This is the point where
thread safety comes to mind.
libvirt stores errors in thread-local-storage. It uses
pthread_key_create/pthread_{get,set}specific for this (or
TlsAlloc/Tls{Get,Set}Value on Windows).
I think what's happening here is that all your threads in Java share
the same thread-local-storage. Therefore, thread A can pickup the
error triggered by thread B, that should not happen.
That could only happen if the JVM was using green threads instead of
native threads, but no serious JVM still uses green threads these days.
Daniel
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