Feature #9963: Symbol.count

• Status: Feedback
• Priority: Normal
• Assignee: -
• Target version: -

[davidcornu (David Cornu)]

I'd like to add a way to get the size of Ruby's symbol table. This is currently possible by using Symbol.all_symbols, however it builds a new array every time it's invoked which is pretty inefficient.

The main use case for this would be to assist in detecting accidental symbol creation.

I have a PR open (https://github.com/ruby/ruby/pull/639) that adds a Symbol.count method but this could also be added in the output of GC.stat.

[kosaki (Motohiro KOSAKI)]

I understand symbol table detection is important for tuning ruby nowadays. But as far as I know, it is just because past ruby can't gc symbols.

Now, ruby trunk has symbol GC. (https://bugs.ruby-lang.org/issues/9634).
So, symbol table size is no longer important tuning parameter.

If you have another use case, please elaborate more detail.

[davidcornu (David Cornu)]

Now, ruby trunk has symbol GC

Fantastic!

[hsbt (Hiroshi SHIBATA)]

• Status changed from Open to Feedback

[akr (Akira Tanaka)]

• Related to Feature #11158: Introduce a Symbol.count API as a more efficient alternative to Symbol.all_symbols.size added