I also think it's an upgrade artifact. It happened on my upgraded laptop but not in the freshly installed desktop machine. The problem in the laptop now (I think) hostapd that requires dnsmasq. The workaround cited by @ahasenack in #49 seems to work.
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dnsmasq in Ubuntu. https://bugs.launchpad.net/bugs/1670959 Title: systemd-resolved using 100% CPU Status in dnsmasq package in Ubuntu: Confirmed Status in systemd package in Ubuntu: Confirmed Bug description: Sometimes systemd-resolved process is using 100% CPU. After a while it changes back to normal. It happens usually after connecting to the (wifi) network, like starting the OS. strace output: sendmsg(12, {msg_name(16)={sa_family=AF_INET, sin_port=htons(33589), sin_addr=inet_addr("127.0.0.1")}, msg_iov(1)=[{"6\215\201\200\0\1\0\1\0\0\0\1\4cs41\3wac\vedgecastcdn\3net\0\0\34\0\1\300\f\0\34\0\1\0\0\10\235\0\20&\6(\0\0024\0Y%L\4\6#f&\214\0\0)\377\326\0\0\0\0\0\0", 81}], msg_controllen=28, [{cmsg_len=28, cmsg_level=SOL_IP, cmsg_type=IP_PKTINFO, {ipi_ifindex=if_nametoindex("lo"), ipi_spec_dst=inet_addr("127.0.0.53"), ipi_addr=inet_addr("127.0.0.53")}}], msg_flags=0}, 0) = 81 sendmsg(3, {msg_name(0)=NULL, msg_iov(4)=[{"PRIORITY=6\nSYSLOG_FACILITY=3\nCODE_FILE=../src/resolve/resolved-dns-stub.c\nCODE_LINE=363\nCODE_FUNCTION=dns_stub_process_query\nSYSLOG_IDENTIFIER=systemd-resolved\n", 160}, {"MESSAGE=", 8}, {"Processing query...", 19}, {"\n", 1}], msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 188 epoll_wait(4, [{EPOLLIN, {u32=3176459184, u64=94565471415216}}], 16, -1) = 1 clock_gettime(CLOCK_BOOTTIME, {44665, 938069872}) = 0 recvfrom(12, NULL, 0, MSG_PEEK|MSG_TRUNC, NULL, NULL) = 53 recvmsg(12, {msg_name(16)={sa_family=AF_INET, sin_port=htons(33589), sin_addr=inet_addr("127.0.0.1")}, msg_iov(1)=[{"Z\262\1\20\0\1\0\0\0\0\0\1\4cs41\3wac\vedgecastcdn\3net\0\0\34\0\1\0\0)\2\0\0\0\0\0\0\0", 3936}], msg_controllen=56, [{cmsg_len=28, cmsg_level=SOL_IP, cmsg_type=IP_PKTINFO, {ipi_ifindex=if_nametoindex("lo"), ipi_spec_dst=inet_addr("127.0.0.53"), ipi_addr=inet_addr("127.0.0.53")}}, {cmsg_len=20, cmsg_level=SOL_IP, cmsg_type=IP_TTL, {ttl=64}}], msg_flags=0}, 0) = 53 stat("/etc/resolv.conf", {st_mode=S_IFREG|0644, st_size=303, ...}) = 0 getrandom("\365I", 2, GRND_NONBLOCK) = 2 stat("/etc/resolv.conf", {st_mode=S_IFREG|0644, st_size=303, ...}) = 0 getrandom("\203;", 2, GRND_NONBLOCK) = 2 clock_gettime(CLOCK_BOOTTIME, {44665, 938446937}) = 0 open("/run/systemd/netif/links/3", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) stat("/etc/resolv.conf", {st_mode=S_IFREG|0644, st_size=303, ...}) = 0 stat("/etc/resolv.conf", {st_mode=S_IFREG|0644, st_size=303, ...}) = 0 socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, IPPROTO_IP) = 18 connect(18, {sa_family=AF_INET, sin_port=htons(53), sin_addr=inet_addr("127.0.0.1")}, 16) = 0 epoll_ctl(4, EPOLL_CTL_ADD, 18, {EPOLLIN, {u32=3176610576, u64=94565471566608}}) = 0 write(18, "\203;\1\20\0\1\0\0\0\0\0\1\4cs41\3wac\vedgecastcdn\3net\0\0\34\0\1\0\0)\2\0\0\0\0\0\0\0", 53) = 53 clock_gettime(CLOCK_BOOTTIME, {44665, 938833717}) = 0 clock_gettime(CLOCK_BOOTTIME, {44665, 938875138}) = 0 epoll_ctl(4, EPOLL_CTL_DEL, 18, NULL) = 0 close(18) = 0 journalctl output: Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:35 parsec systemd-resolved[1512]: Processing query... Mar 08 08:25:41 parsec dnsmasq[1545]: Maximum number of concurrent DNS queries reached (max: 150) As you can see, I would use it together with dnsmasq. ProblemType: Bug DistroRelease: Ubuntu 17.04 Package: systemd 232-18ubuntu1 ProcVersionSignature: Ubuntu 4.10.0-9.11-generic 4.10.0 Uname: Linux 4.10.0-9-generic x86_64 NonfreeKernelModules: zfs zunicode zavl zcommon znvpair ApportVersion: 2.20.4-0ubuntu2 Architecture: amd64 Date: Wed Mar 8 08:20:18 2017 MachineType: Hewlett-Packard HP EliteBook Folio 1020 G1 ProcEnviron: LANGUAGE=en_US:en TERM=xterm PATH=(custom, no user) LANG=en_US.UTF-8 SHELL=/bin/zsh ProcKernelCmdLine: BOOT_IMAGE=/@/boot/vmlinuz-4.10.0-9-generic root=UUID=a54fe703-35d4-47ac-9c6e-4034421531fb ro rootflags=subvol=@ SourcePackage: systemd UpgradeStatus: Upgraded to zesty on 2015-05-24 (653 days ago) dmi.bios.date: 03/09/2015 dmi.bios.vendor: Hewlett-Packard dmi.bios.version: M77 Ver. 01.05 dmi.board.name: 2271 dmi.board.vendor: Hewlett-Packard dmi.board.version: KBC Version 91.4C dmi.chassis.asset.tag: CNU51199KV dmi.chassis.type: 10 dmi.chassis.vendor: Hewlett-Packard dmi.modalias: dmi:bvnHewlett-Packard:bvrM77Ver.01.05:bd03/09/2015:svnHewlett-Packard:pnHPEliteBookFolio1020G1:pvrA3009DD18303:rvnHewlett-Packard:rn2271:rvrKBCVersion91.4C:cvnHewlett-Packard:ct10:cvr: dmi.product.name: HP EliteBook Folio 1020 G1 dmi.product.version: A3009DD18303 dmi.sys.vendor: Hewlett-Packard To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/dnsmasq/+bug/1670959/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
