| RE: [aspectj-users] OutOfMemryError LTW |
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RE: [aspectj-users]
OutOfMemryError LTW
Wow, that does chew up quite a bit of memory.
How are you able to estimate the size of the heap thats required? I usually
hit errors when I try enable both LTW and a profiler like Netbeans Profiler
because both javaagents are trying to hotswap classes
Ron Bodkin <rbodkin@xxxxxxxxxxxxxx> wrote:
Hi Eric,
AspectJ load-time weaving is
still quite memory intensive although it has improved a lot since 1.5.0.
For example, I found that starting Tomcat with some small applications
without AspectJ load-time weaving requires 11mb of heap and 18 mb of non-heap
memory. If I deploy a development version of Glassbox with AspectJ 1.5.2
rc1, it requires 41 mb of heap and 23 mb of non-heap memory. (*)
In the meanwhile, one technique
you can use to limit memory use by the weaver is to use the include type
patterns to only weave into code you need to affect. E.g., if you have
an application specific aspect, if you add <include within=â€com.myco.myapp..*â€/>
to your META-INF/aop.xml then you should find a much lower memory overhead.
(*) I am working on two ideas
for improving this situation:
* The patch submitted with
AspectJ enhancement #148773 reduces the heap required to 33 mb
* Allowing loading common aspect
definitions once per system instead of many times with many copies. Memory
profiles show me that most of the overhead is pinned by having 10 copies
of the weaving definitions one for each ClassLoader affected. This could
also reduce the time overhead for weaving, too. The tricky part about doing
this is to support nondelegating ClassLoaders that provide a different
definition of parent types.
Hope that Helps,
Ron