RFR: 8207263: Store the Configuration for system modules into CDS archive
jiangli.zhou at oracle.com
Wed Aug 8 23:43:26 UTC 2018
Thanks Claes for resolving JDK-8209003 quickly. Here is my updated
weberv that includes following changes:
- Added archiving for singletons in ImmutableCollections
(ListN.EMPTY_LIST, SetN.EMPTY_SET and MapN.EMPTY_MAP). Please see
changes in ImmutableCollections.java.
- Incorporated Calvin and Ioi feedbacks on vmSymbols.hpp.
- Added a new test case to check the parents and modules of archived
- Added argument length check in CheckArchivedModuleApp.java test as
On 8/6/18 9:48 AM, Jiangli Zhou wrote:
> 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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