[tor-relays] Memory Problems with tor releay

[Roger Dingledine]

On Mon, May 22, 2017 at 10:48:31PM +0200, niftybunny wrote:
> Same with 0.3.0.5. Upgrading to 0.3.0.7 helped on most relays. 

We didn't change anything between 0.3.0.5 and 0.3.0.7 that would
have helped.

If somebody with a really really fast CPU wants to run their relay under
valgrind --leak-check for a while, that would be grand.

https://gitweb.torproject.org/tor.git/tree/doc/HACKING/HelpfulTools.md

The question to try to get some answers on is what sort of bloat problem
we have:

A) Maybe it's a memory leak?

B) Maybe it's an inefficiency of the memory allocator, e.g. fragmentation
where nothing is technically leaked yet there's a whole lot of wasted
space?

C) Maybe it is some behavior by clients that causes the relay to use a
lot of memory, e.g. by having a bunch of stuff in buffers? The behavior
could be accidental / normal, or it could be intentional / malicious.

My first guess is "C, accidental". But it could easily be 'B', and it
would be great if it's 'A' because then we can just fix it.

--Roger