RFR: 8207263: Store the Configuration for system modules into CDS archive
jiangli.zhou at oracle.com
Mon Aug 6 16:48:51 UTC 2018
Hi Calvin and Ioi,
Thanks for reviewing the change! I'll incorporate your suggestions.
As Claes pointed out in his email, there was a subtle issue with the
empty configuration, which was undetected by the testing for archiving
changes but could introduce a bug in certain cases. Claes has already
filed JDK-8209003 for consolidating empty collections usage in module
code. I'll look into archiving the immutable singletons in
On 8/3/18 2:58 PM, Ioi Lam wrote:
> 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,
>> 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")
> - 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.
>> 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.
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