On 01/24/2013 03:34 PM, Peter Levart wrote:
On 01/24/2013 03:10 PM, Alan Bateman wrote:
On 24/01/2013 13:49, Peter Levart wrote:
Should I file a RFE first?
Sorry I don't have time at the moment to study the proposed patch but
just to mention that it has come up a few times, its just that it
never bubbled up to the top of anyone's list. Here's the bug tracking
it:
http://bugs.sun.com/view_bug.do?bug_id=7123493
-Alan.
I belive that is another bottleneck. It is mentioning the
Proxy.getProxyClass method which also uses synchronization for
maintaining a cache of proxy classes by request parameters. I could as
well try to fix this too in the same patch if there is interest.
Regards, Peter
Hi Alan, David,
I thought about the ways to fix Proxy.isProxyClass() scalability and the
Proxy.getProxyClass() scalability. While they are different methods,
each with it's own data structure, I think that both problems can be
solved with a single solution and that solution does not involve neither
adding fields to j.l.Class nor ClassValue.
The solution is actually very simple. I just want to validate my
reasoning before jumping to implement it:
- for solving scalability of getProxyClass cache, a field with a
reference to ConcurrentHashMap<List<String>, Class<? extends Proxy>> is
added to j.l.ClassLoader
- for solving scalability of isProxyClass, a field with a reference to
ConcurrentHashMap<Class<? extends Proxy>, Boolean> is added to
j.l.ClassLoader
Both maps hold strong references to Class objects, but only for the
classes that are loaded by the ClassLoader that references them. Each
ClassLoader already holds a strong reference to all the Class objects
for the classes that were loaded by it in a Vector. Holding another
reference does not present any problem, right?
I think this would be the best solution and it would solve both
scalability problems of j.l.Proxy in one go.
Am I missing something?
Regards, Peter
