RFR (M): (7u60): Backport of 8027476: Improve performance of Stringtable unlink, 8027455: Improve symbol table scan times during gc pauses

[Mikael Gerdin]

Thomas,

On Wednesday 29 January 2014 17.09.51 Thomas Schatzl wrote:
> Hi Mikael,
> 
> On Tue, 2014-01-28 at 15:00 +0100, Mikael Gerdin wrote:
> > Thomas,
> > 
> > On Tuesday 28 January 2014 11.57.33 Thomas Schatzl wrote:
> > > Hi,
> > > 
> > >   I got the link for the new webrev wrong, taking two from the original
> > >   
> > > > These differences are contained in symbolTable.?pp, the rest is
> > > > verbatim backport iirc.
> > > > 
> > > > New webrev:
> > > > http://cr.openjdk.java.net/~tschatzl/8027476/webrev
> > > 
> > > Correct webrev is at:
> > > 
> > > http://cr.openjdk.java.net/~tschatzl/8027476.7u60/webrev
> > 
> > symbolTable.cpp:
> >  103       Symbol* s = entry->literal();
> >  104       memory_total += s->object_size(); << should be (*memory_total)
> >  +=
> >  105       (*processed)++;
> > 
> > g1ColletedHeap.cpp:
> > 
> > 5237     guarantee(StringTable::parallel_claimed_index() >=
> > _initial_string_table_size,
> > 5238               err_msg("claim value "INT32_FORMAT" after unlink less
> > than initial string table size "INT32_FORMAT,
> > 5239                       StringTable::parallel_claimed_index(),
> > _initial_string_table_size));
> > 5240     guarantee(!_process_strings ||
> > SymbolTable::parallel_claimed_index()> 
> > >= _initial_symbol_table_size,
> > 
> > 5241               err_msg("claim value "INT32_FORMAT" after unlink less
> > than initial symbol table size "INT32_FORMAT,
> > 5242                       SymbolTable::parallel_claimed_index(),
> > _initial_symbol_table_size));
> > 5243
> > 
> > You've removed the !_process_strings from the guarantee compared to 9.
> > Also, I noticed that the 9 versions has !_process_strings in both
> > guarantees although I think the second one should be !_process_symbols.
> 
> All fixed in the new webrev at
> http://cr.openjdk.java.net/~tschatzl/8027476.7u60/webrev.1/
> 
> Thanks a lot.

The change looks good now.
/Mikael

> 
> I will file a bug for 8u20 and 9.
> 
> Thanks,
>   Thomas