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From Gregory Shimansky <gshiman...@apache.org>
Subject Re: [VM] On-demand class library parsing is ready to commit
Date Tue, 23 Dec 2008 13:04:00 GMT
Wenlong Li said the following on 23.12.2008 15:59:
> Gregory,
> VM creation module includes function call to parse jar file and
> load&initialize necessary classes stuffs. You can refer to the
> vm_init1() and vm_init2() for detail.

Ok I see. I didn't read the thread well enough before replying. Sorry 
for confusion.

> On Tue, Dec 23, 2008 at 8:01 PM, Gregory Shimansky
> <gshimansky@apache.org> wrote:
>> Pavel Pervov said the following on 23.12.2008 10:34:
>>> Guys,
>>> Why you are in need of instrumentation?
>>> You only want to measure the time spent in JNI_CreateJavaVM method. It
>>> is very-very simple to create C-program which utilizes invocation API
>>> to call to JNI_CreateJavaVM and calls to performance counters before
>>> and after VM creation to calculate that time. This will be exactly the
>>> "startup-time" according to Wenlong. Then you can run it through the
>>> script supplied by Aleksey.
>>> If you also want to include finding main class - you can look into our
>>> launcher and borrow the code from there.
>>> Invocation API rules. ;)
>> I don't quite agree. With lazy resolution CreateJavaVM doesn't really
>> execute most of Java code that is required to load user program and execute
>> all of the necessary code of system class loader which parses jar files and
>> stuff like that. This code is what takes the most time on startup.
>> --
>> Gregory


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