From: Daniel Berger <djberg96@...>
Date: 2008-02-22T06:18:00+09:00
Subject: Re: GC error ?



On Feb 21, 1:51 pm, Yukihiro Matsumoto <m...@ruby-lang.org> wrote:
> Hi,
>
> In message "Re: GC error ?"
>     on Fri, 22 Feb 2008 05:17:03 +0900, "Rick DeNatale" <rick.denat...@gmail.com> writes:
>
> |Yes, and it also suffers from two facts that make it perform
> |sub-optimally on a virtual memory system (i.e. just about any system
> |these days)
> |
> |1) It fails to compact the live objects
> |2) It pretty much is guaranteed to visit every memory page at least
> |twice per GC cycle.
>
> Indeed, we need two visits (one write to mark live objects/one read to
> sweep dead objects) per GC.  But using bitmap marking technique[1],
> objects visit can be reduced to one.
>
> [1]http://izumi.plan99.net/blog/index.php/2008/01/14/making-ruby%e2%80%9...

When I applied Izumi's patch to the 1.8.x branch it took a ~20%
performance hit.

Have you benchmarked before and after for 1.9?

Regards,

Dan