Hi David, On 22/10/2014 15:21, David Zafman wrote:> > I just realized what it is. The way killall is used when stopping a vstart cluster, is to kill all processes by name! You can't stop vstarted tests running in parallel. I discovered this indeed. But then instead of using ./stop.sh I use https://github.com/dachary/ceph/blob/6e6ddfbdc0a178a6318a86fd9984265bbe40ca3d/src/test/mon/mon-test-helpers.sh#L62 in the context of https://github.com/dachary/ceph/blob/6e6ddfbdc0a178a6318a86fd9984265bbe40ca3d/src/test/vstart_wrapper.sh#L28 which makes it kill only the processes with a pid file in the relevant directory. The problem bellow showed because it was doing an aggressive kill -9 to check if the process still exists. https://github.com/dachary/ceph/commit/6e6ddfbdc0a178a6318a86fd9984265bbe40ca3d Now that it's replaced with a kill -0 all is well. For the record the problem can be reliably reproduced by running make -j8 check from https://github.com/dachary/ceph/commit/c02bb8a5afef8669005c78b2b4f2f762cda4ee73 and waiting less than one hour and probably more than 30 minutes on a 24 core, 64GB RAM, 250GB SSD disk. Cheers > > David Zafman > Senior Developer > http://www.inktank.com > > > > >> On Oct 21, 2014, at 7:55 PM, Loic Dachary <loic@xxxxxxxxxxx> wrote: >> >> Hi, >> >> Something strange happens on fedora20 with linux 3.11.10-301.fc20.x86_64. Running make -j8 check on https://github.com/ceph/ceph/pull/2750 a process gets killed from time to time. For instance it shows as >> >> TEST_erasure_crush_stripe_width: 124: stripe_width=4096 >> TEST_erasure_crush_stripe_width: 125: ./ceph osd pool create pool_erasure 12 12 erasure >> *** DEVELOPER MODE: setting PATH, PYTHONPATH and LD_LIBRARY_PATH *** >> ./test/mon/osd-pool-create.sh: line 120: 27557 Killed ./ceph osd pool create pool_erasure 12 12 erasure >> TEST_erasure_crush_stripe_width: 126: ./ceph --format json osd dump >> TEST_erasure_crush_stripe_width: 126: tee osd-pool-create/osd.json >> >> in the test logs. Note the 27557 Killed . I originally thought it was because some ulimit was crossed and set them to very generous / unlimited hard / soft thresholds. >> >> core file size (blocks, -c) 0 >> data seg size (kbytes, -d) unlimited >> scheduling priority (-e) 0 >> file size (blocks, -f) unlimited >> pending signals (-i) 515069 >> max locked memory (kbytes, -l) unlimited >> max memory size (kbytes, -m) unlimited >> open files (-n) 400000 >> pipe size (512 bytes, -p) 8 >> POSIX message queues (bytes, -q) 819200 >> real-time priority (-r) 0 >> stack size (kbytes, -s) unlimited >> cpu time (seconds, -t) unlimited >> max user processes (-u) unlimited >> virtual memory (kbytes, -v) unlimited >> file locks (-x) unlimited >> >> Benoit Canet suggested that I installed systemtap ( https://www.sourceware.org/systemtap/wiki/SystemtapOnFedora ) and ran https://sourceware.org/systemtap/examples/process/sigkill.stp to watch what was sending the kill signal. It showed the following: >> >> ... >> SIGKILL was sent to ceph-osd (pid:27557) by vstart_wrapper. uid:1001 >> SIGKILL was sent to python (pid:27557) by vstart_wrapper. uid:1001 >> .... >> >> which suggests that pid 27557 used by ceph-osd was reused for the python script that was killed above. Because the script that kills daemons is very agressive and kill -9 the pid to check if it really is dead >> >> https://github.com/ceph/ceph/blob/giant/src/test/mon/mon-test-helpers.sh#L64 >> >> it explains the problem. >> >> However, as Dan Mick suggests, reusing pid quickly could break a number of things and it is a surprising behavior. Maybe something else is going on. A loop creating processes sees their pid increasing and not being reused. >> >> Any idea about what is going on would be much appreciated :-) >> >> Cheers >> >> -- >> Loïc Dachary, Artisan Logiciel Libre >> >> > > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Loïc Dachary, Artisan Logiciel Libre
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