The issue is with the systemd resolver not with glibc. With systemd-resolve IP in /etc/resolv.conf:
# This file is managed by man:systemd-resolved(8). Do not edit. # # 127.0.0.53 is the systemd-resolved stub resolver. # run "systemd-resolve --status" to see details about the actual nameservers. nameserver 127.0.0.53 $ time ./test not-a-hostname Trying to resolve: not-a-hostname getaddrinfo errno: No such file or directory getaddrinfo() return value: -2 (Name or service not known) real 0m10.076s user 0m0.001s sys 0m0.000s Without systemd-resolve in /etc/resolv.conf. I changed it to point to my local DNS server directly. # This file is managed by man:systemd-resolved(8). Do not edit. # # 127.0.0.53 is the systemd-resolved stub resolver. # run "systemd-resolve --status" to see details about the actual nameservers. #nameserver 127.0.0.53 nameserver 192.168.1.1 $ time ./test not-a-hostname Trying to resolve: not-a-hostname getaddrinfo errno: No such file or directory getaddrinfo() return value: -2 (Name or service not known) real 0m0.097s user 0m0.001s sys 0m0.000s ** Changed in: glibc (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1739672 Title: Regression in getaddrinfo(): calls block for much longer on Bionic (compared to Xenial) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/glibc/+bug/1739672/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs