This happens (or used to happen) also in 16.04.2 (current). I paste here a couple of evidences (17.04):
$ ps auxwww | grep ping sgala 12545 96.5 0.0 20592 1020 pts/2 R+ 13:18 118:36 ping 192.168.25.96 (...) $ sudo strace -p 12545 (...) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) recvmsg(3, 0x7ffe0a5d0b00, MSG_DONTWAIT) = -1 EAGAIN (Resource temporarily unavailable) poll([{fd=3, events=POLLIN|POLLERR}], 1, 164) = 1 ([{fd=3, revents=POLLERR}]) (...) The ping is taking 100% CPU. After I killed the process, one can see that the command line was a plain "ping 192.168.25.96" About ping version: $ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=17.04 DISTRIB_CODENAME=zesty DISTRIB_DESCRIPTION="Ubuntu 17.04" $ dpkg -l $(dpkg-query -S $(which ping) | awk -F: '{print $1}') Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Architecture Description +++-=================================-=====================-=====================-======================================================================= ii iputils-ping 3:20161105-1ubuntu2 amd64 Tools to test the reachability of network hosts I have also seen this going on with Ubuntu 16.04.2 LTS fully patched. I use something like ((ping -i 60 -B [address] >& /dev/null )&)& as a poor man's keepalive, and it jumps systematically to 100% CPU after one or two days. Versions for 16.04.2: $ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=16.04 DISTRIB_CODENAME=xenial DISTRIB_DESCRIPTION="Ubuntu 16.04.2 LTS" $ dpkg -l $(dpkg-query -S $(which ping) | awk -F: '{print $1}') Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Architecture Description +++-=================================-=====================-=====================-======================================================================= ii iputils-ping 3:20121221-5ubuntu2 amd64 Tools to test the reachability of network hosts Note there has been some time since I last observed the bug in 16.04.2, but I have just found my laptop spinning before I decided to look for the bug and post here. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1697646 Title: Long-running ping command leads to 100% CPU usage To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/iputils/+bug/1697646/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs