RFR(L): 8029075 - String deduplication in G1

[Thomas Schatzl]

Hi again,

  some comment below...

On Wed, 2014-03-05 at 11:56 +0100, Thomas Schatzl wrote:
> Hi Per,
> 
> On Mon, 2014-03-03 at 14:33 +0100, Per Liden wrote:
> > Hi,
> > 
> > Could I please have this patch reviewed.
> 
>   this is not a complete review (still working on it), but some comments
> about measuring the time taken.
> 
> When printing thread processing times, is it possible to provide
> per-thread times for the specific parts (queue processing, table
> processing) and the total?
> 
> E.g. instead of only the total time for weak root fixup, provide also
> string table processing time.
> 
> This would help finding issues with particular phases of the weak root
> fixup, and in particular string dedup. Per thread times (at maximum
> logging level) will help finding issues. 
> 
> Potentially this code is trying to distribute little work on hundreds of
> threads after all and this would help identifying the problem quickly.
> 
> Something like:
> 
> [Weak Root Fixup ....]
>   [String Dedup ...]

Probably it's better that this change only adds the String Dedup entry.

> 
> (Additionally, probably better in a separate CR, add timing for
> processing the JNI weak root handles).

That separate CR should probably add both "Weak Root Fixup" and "JNI
Handle Fixup" entries.

Thanks,
  Thomas