From: Aman Gupta <ruby@...1.net>
Date: 2013-04-18T06:02:42+09:00
Subject: [ruby-core:54408] Re: frozen strings (was: [patch] reduce allocations due to __FILE__ ...)

On Wed, Apr 17, 2013 at 11:49 AM, Eric Wong <normalperson@yhbt.net> wrote:
> "headius (Charles Nutter)" <headius@headius.com> wrote:
>> I'd like to work with you to find more places we could be sharing
>> frozen strings. A change over the summer made defined? results always
>> be shared frozen strings, and apparently that was a source of lots and
>> lots of extra string creation in Rails (according to wycats). There's
>> many other such opportunities.
>
> I've considered (but never got around to implementing/testing) caching
> for rb_str_dup_frozen.  This might help with hashes which use common
> strings as keys (e.g. CGI params and HTTP headers).
>
> Perhaps one of you can experiment with this before I can get around
> to it..
>

I actually started on this a few weeks ago. I added a frozen string
cache and was able to remove a large number of duplicated strings from
the Ruby heap.

I'll clean up the patch and open a redmine issue for review.

  Aman