TCP_BACKLOG runtime config option

[SvenVD-be]

Is there any way to increase the default TCP_BACKLOG option of nsd from 256 to higher values without recompiling and setting the value higher in AC_DEFINE_UNQUOTED([TCP_BACKLOG], [256]?

It would be nice if this was a configuration option like the tcp-listen-queue that bind has.

Thanks

[wtoorop]

Thanks @SvenVD-be . We'll consider (I'll bring it up internally).

[crrodriguez]

On Linux you should default to -1 (meaning OS default or sysadmin choosen value) not to an arbitrary number you picked.

[crrodriguez]

see also https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=19f92a030ca6d772ab44b22ee6a01378a8cb32d4

[SvenVD-be]

any update?

[k0ekk0ek]

Hi @SvenVD-be! Sorry for the overdue reply. Looking at the code, there are no changes yet. I don't know what was decided at the time. @wtoorop or @wcawijngaards any comments? If there's no objections, I guess it isn't too much work to add the option and the -1 option indicated by @crrodriguez may actually be a good default, at least on Linux.

[wcawijngaards]

I do not recall, @k0ekk0ek . I also have no objections, for this option. Most DNS authority servers have very little TCP traffic, because they use UDP.