[Dnsmasq-discuss] [BUG] RA are sent too fast and slows down the machine

[Simon Kelley]

On 21/08/2019 19:59, Petr Mensik wrote:
> Hi Simon and Maarten,
> 
> we discovered when playing with NetworkManager-ci [1], that lastest
> release is somehow broken. Test running dnsmasq are quite slow on latest
> release.
> 
> I have created repeatable started script that reproduces it. Then used
> git bisect to find when it was broken. It seems fast sending were
> intentional in commit 0a496f059c1e9 [2], but maybe way it affects the
> system were underestimated. It is significant for systems that hit such
> issue. I think it has to be fixed to slow it down to short time
> interval, not endless loop. Reported as Fedora bug [3].
> 
> 1. https://github.com/NetworkManager/NetworkManager-ci
> 2.
> http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commit;h=0a496f059c1e9d75c33cce4c1211d58422ba4f62
> 3. https://bugzilla.redhat.com/show_bug.cgi?id=1739797
> 

Petr,

returning to this after too long away, I've committed what seems like
the most sensible fix:


http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commit;h=515ba97595e60c762c448657f3c0e545c1e365f9

which is different from yours. It only starts fast-RA when the
dhcp-range in question has never been used before. This satisfies the
original aim of 0a496f059c1e9d75c33cce4c1211d58422ba4f62 but eliminates
the possibility of the infinite loop.

Does that work for you?


Simon.