[zeromq-dev] Improving zeromq in OOM conditions

[Martin Sustrik]

Hi Paul,

> Done.

Ok. Applied to master. Thanks!

> Can you give me a better advice. Do you think connection shouldn't be
> closed on OOM first, or is it better to leave that intact and refactor
> reconnection code to not crash in the first place? BTW, current
> connection closing code is helpful for debuging latter.

What I personally believe is that the library should not get to OOM 
condition in the first place. Possible steps to get that would include:

1. Use finite default HWM.
2. Use finite default MAXMSGSIZE.
3. Implement a MAXCONNECTIONS option with finite default.
4. Think hard about whether it makes sense to allow infinite as an valid 
option for any of the above.

However, that's my personal opinion. If you still feel like you should 
handle the OOM situation when it hits, feel free to try. However, don't 
do any guesswork. With OOM handling the guesses mostly turn out to be 
false. Make a test instead and fix the problem you'll get.

Also keep in mind that your sophisticated OOM handling is likely to be 
spoiled by OS OOM killer hitting in and killing the whole process.

Martin