Re: [Sbcl-devel] allocating really large strings leads to heap exhaustion

[Juho S. <js...@ik...>]

"David J. Neu" <dav...@gm...> writes:
> Hi Juho,
> 
> Would your patch address, the following issue mentioned in
> http://article.gmane.org/gmane.lisp.steel-bank.devel/10194/?
> 
> * how to explain why Lisp lets itself get into a place where it  
> cannot recover memory. All of the memory allocated during the call to  
> parse-text is garbage; it can all be freed. But both SBCL and Allegro  
> are unable to freed the memory without running out of memory during  
> the process.

No. The GC would still be copying, which means that in the worst case
(no garbage, memory being used by "small" objects of less than 16kB
each) you need to have double the heap compared to the working set.
And given UCS-4 strings, the problem being discussed in that thread
would have approximately a 1GB working set -> it'd run out of memory
unless you have at least a 2GB heap.

-- 
Juho Snellman