RFR(S) 8246181: Avoid walking SymbolTable during -Xshare:dump

[Yumin Qi]

Hi, Ioi

Thanks for the review and bug cleaning.


Thanks

Yumin


On 6/23/20 3:45 PM, Ioi Lam wrote:
> Hi Yumin,
>
> The changes look good.
>
> I updated the bug description to the following:
>
>     Walking the symbol table during static dump time is
>     problematic (see JDK-8245264). Since all Symbols are marked
>     as permanent during static dumping, we can just save all of
>     them in a global array as they are created, and walk this
>     array during the dump process.
>
> I moved the original proposal into a comment in JDK-8246181. That 
> proposal
> should be implemented as part of JDK-8234693 (Consolidate CDS static and
> dynamic archive dumping code)
>
>
> Thanks
> - Ioi
>
>
> On 6/23/20 2:44 PM, Yumin Qi wrote:
>> Hi, Please review
>>
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8246181
>>
>> Webrev:http://cr.openjdk.java.net/~minqi/2020/8246181/webrev-00/
>>
>>
>> Summary: This is a little different from the bug suggested 
>> implementation. To avoid working the SymbolTable during dump, the 
>> symbol is added to a global array when it is created, 
>> SymbolTable::do_add_if_needed. The symbol only created once during 
>> its lifetime. There is just little performance overhead for runtime.
>>
>>
>> Tests: local jtreg on runtime/cds/appcds for debug/release.
>>
>> mach5: tier1,tier2,tier4
>>
>>
>> Thanks
>>
>> Yumin
>>
>