Re: Real-World Impact of Hash DoS in Lua

[Roberto Ierusalimschy <roberto@...>]

> > The main reasons we are changing Lua
> > are that we like this idea of long non-internalized strings
> 
> That, I'm not so sure about. I'll freely admit: it does have a
> certain appeal. But I'd want to see convincing, quantitative proof
> that the resulting increase in complexity does not adversely
> affect the performance of the common case. The simplicity of the
> current solution and the resulting stability is a very convincing
> argument against such a big change, too.

Certainly it is. The real interesting thing is that non-internalized
strings open the door for "external" buffers, that is, buffers decopled
form the TString struture. That would allow things like luaL_Buffer
and even lua_concat to use the intermediate buffer as the resulting
string. It would allow large literal strings to point directly to its
fixed version. But simplicity is always a compelling argument.

-- Roberto