Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

dnsdist: Change the default max number of queued TCP conns to 1000 #4596

Merged

Conversation

@rgacogne
Copy link
Member

@rgacogne rgacogne commented Oct 20, 2016

With the existing default value of 0, we could consume an unlimited
number of file descriptors if the queued connections kept piling up.

@rgacogne rgacogne added this to the dnsdist-1.1.0 milestone Oct 20, 2016
@rgacogne
Copy link
Member Author

@rgacogne rgacogne commented Oct 20, 2016

I will check more carefully but it looks like there is a mistake in the way the maximum number of file descriptors is computed:
requiredFDsCount += (tcpBindsCount * g_maxTCPQueuedConnections);
should probably be:
requiredFDsCount += g_maxTCPQueuedConnections;

And dnsdist warns when the current FD limit is less than 4/3 of the maximum FD usage, since some FD can't be accurately predicted, like web and console connections. That formula doesn't work too well for large FD counts, I'm afraid.

rgacogne added 2 commits Oct 24, 2016
With the existing default value of 0, we could consume an unlimited
number of file descriptors if the queued connections kept piling up.
@rgacogne rgacogne force-pushed the dnsdist-default-ma-tcp-queued-conns branch from cfabf6a to 9fcd6ad Oct 24, 2016
@rgacogne rgacogne merged commit 01cfcb9 into PowerDNS:master Oct 26, 2016
1 check passed
@rgacogne rgacogne deleted the dnsdist-default-ma-tcp-queued-conns branch Oct 26, 2016
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
Projects
None yet
Linked issues

Successfully merging this pull request may close these issues.

None yet

1 participant