RFR: 8207263: Store the Configuration for system modules into CDS archive

[Ioi Lam]

On 8/3/18 11:37 AM, Calvin Cheung wrote:
> Hi Jiangli,
>
> The changes look good to me.
>
> I have couple of minor comments:
>
> 1) vmSymbols.hpp
>
>  653   template(url_void_signature, 
> "(Ljava/net/URL;)V")                                           \
>  654   template(toFileURL_name, 
> "toFileURL")                                                   \
>  655   template(toFileURL_signature, 
> "(Ljava/lang/String;)Ljava/net/URL;")
>
> Since you've moved the above lines to after 
> “template(systemModules_signature, …”, I’d suggest rearrange the 
> entire block (lines 652 - 659) in alphabetical order.
>
Hi Jiangli,

I've reviewed the code. It looks like a clean change and it's great to 
make further progress in start-up improvement!

Just a small note on vmSymbols.hpp:  this line can be deleted because 
the symbol is no longer used.

   template(jdk_vm_cds_SharedClassInfo, "jdk/vm/cds/SharedClassInfo")

Thanks
- Ioi

> 2) CheckArchivedModuleApp.java
>
> Since it now expects two input args, I’d suggest checking the number 
> of input args and throw an exception if it is not equal to two.
>
> thanks,
> Calvin
>
> On 7/20/18, 11:31 AM, Jiangli Zhou wrote:
>> Please review the following webrev that archives the system module 
>> boot layer Configuration (including all java objects reachable from 
>> the Configuration) in CDS archive. This is built on top of the 
>> earlier change for JDK-8202035 
>> (https://bugs.openjdk.java.net/browse/JDK-8202035), which provides a 
>> framework for object sub-graph archiving.
>>
>> The boot layer Configuration is created in ModuleBootstrap.boot() 
>> (similar to the archived system ModuleDescriptor objects, etc) and is 
>> unchanged after construction. With archived boot layer Configuration, 
>> it allows runtime to bypass the work for creating the configuration. 
>> Currently, this is only supported when the initial module is unnamed 
>> module. Measurements indicate archiving the boot layer Configuration 
>> improves the startup time by 1% ~ 1.5% (on linux-x64) when running 
>> HelloWorld from -cp at runtime.
>>
>> Many thanks to Alan and Claes for discussions and contributions to 
>> this change!
>>
>> Webrev: http://cr.openjdk.java.net/~jiangli/8207263/webrev.00/
>>
>> RFE: https://bugs.openjdk.java.net/browse/JDK-8207263
>>
>> Tested with tier1 - tier5 tests via mach5.
>>
>> Thanks,
>>
>> Jiangli
>>