RFR (S) 8227123: Assertion failure when setting SymbolTableSize larger than 2^17 (131,072)

[Jiangli Zhou]

Hi Coleen,

On Mon, Jul 22, 2019 at 12:51 PM <coleen.phillimore at oracle.com> wrote:
>
>
> Thanks Jiangli, and for the suggestion to increase the max size.  I was
> waffling about removing the experimental option completely.

Would it be worth considering making SymbolTableSize a product flag?
There was a noticeable performance issue for a large application with
older JDK versions. It was found to be related to slow
SymbolTable::lookup due to too many collisions. Setting a large
initial symbol table size worked around the performance issue and the
improvement was significant. With newer JDK (> 12), user may still
prefer setting a large initial size to avoid any potential overhead
(avoid resizing) for large applications.

Best regards,
Jiangli

> Coleen
>
> On 7/22/19 3:40 PM, Jiangli Zhou wrote:
> > Looks good.
> >
> > Best regards,
> > Jiangli
> >
> > On Mon, Jul 22, 2019 at 11:46 AM <coleen.phillimore at oracle.com> wrote:
> >> Summary: Increase max size for SymbolTable and fix experimental option
> >> range.  Make experimental options trueInDebug so they're tested by the
> >> command line option testing
> >>
> >> open webrev at http://cr.openjdk.java.net/~coleenp/2019/8227123.01/webrev
> >> bug link https://bugs.openjdk.java.net/browse/JDK-8227123
> >>
> >> Tested locally with default and -XX:+UseZGC since ZGC has a lot of
> >> experimental options.  I didn't test with shenanodoah.
> >>
> >> I will test with hs-tier1-3 before checking in.
> >>
> >> Thanks,
> >> Coleen
>