Re: the ...-unload-hook convention doesn't work

[Simon Josefsson <jas@extundo.com>]

Dave Love <d.love@dl.ac.uk> writes:

> As it happens, I do occasionally unload a Gnus feature which leaks.
> That typically reduces the number of used conses from ~1M to ~300k and
> means GC then doesn't typically thrash on my work system though it
> leaves a lot of unused ones.

Which feature is this?  Any hints on finding leaking code, in general?
I have been using the following to print out large symbols:

(mapatoms (lambda (sym)
	    (let ((len (ignore-errors (length (symbol-value sym)))))
	      (if (and len (> len 500) (not (= len 507904)))
		  (insert (format "%s: %s\n" sym len))))))

But it doesn't seem to work well.  I have been getting complaints
about exhausting the memory from Emacs without that code generating
anything interesting.  My machine has 1 GB RAM, and emacs is typically
around 100MB but can grow to 300MB or so when I do something major in
Gnus.

Essentially: how do I find out what is taking up all memory in Emacs?
Perhaps a package that report these things would be handy.