On 11/01/2013 10:11 PM, Mandy Chung wrote:
On 11/1/13 1:37 PM, [email protected] wrote:
2013/11/1 4:15 -0700, [email protected]:
http://cr.openjdk.java.net/~mchung/jdk8/webrevs/8027351/webrev.00/
Looks good.
Just one question: In Finalizer.java, at line 97 you look up the
JavaLangAccess object every single time. Is it worth caching that
earlier, maybe when the finalize thread starts, since it will never
change?
I was expecting that would get optimized during runtime and it's a
simple getter method. It's a good suggestion to cache it at the
finalize thread start time and here is the revised webrev:
http://cr.openjdk.java.net/~mchung/jdk8/webrevs/8027351/webrev.01/
Thanks for the review.
Mandy
Hi Mandy,
FWIW, I don't know if you gain anything by caching static field in a
static field, performance wise.It looks nicer at use site though. If
performance was really extremely important in this use case (which I
think is not) then "jla" should be a local variable inside
FinalizerThread.run() (and possibly in the anonymous Runnables too) and
passed as an argument to Finalizer.runFinalizer().
Looking at code once more, I see a possible data race. Is it remotely
possible, that either Finalizer.runFinalization() or
Finalizer.runAllFinalizers() is executed and new secondary finalizer
thread spawned and executed before FinalizerThread manages to call
ensureAccessAvailable(), therefore executing the
Finalizer.runFinalizer() methods before static Finalizer.jla is
initialized? Even though jla field was initialized, what guarantees it's
value being visible in spawned secondary finalizer threads?
FinalizerThread is started in Finalizer's static initializer, yes, but
ensureAccessAvailable() is called by FinalizerThread after it starts...
Considering all this, it might be safer to just ready the SharedSecrets
field every time it's needed.
Regards, Peter
