[ovs-dev] [PATCH] ovs-vsctl: Change log level of vsctl_parent_process_info

[Kyle Mestery]

On Thu, Aug 4, 2016 at 3:38 PM, Andy Zhou <azhou at ovn.org> wrote:
>
>
> On Thu, Aug 4, 2016 at 11:39 AM, Kyle Mestery <mestery at mestery.com> wrote:
>>
>> On Thu, Aug 4, 2016 at 12:56 PM, Andy Zhou <azhou at ovn.org> wrote:
>> >
>> >
>> > On Thu, Aug 4, 2016 at 6:54 AM, Kyle Mestery <mestery at mestery.com>
>> > wrote:
>> >>
>> >> While running the ovn-scale-test [1] port-binding tests [2], I notice a
>> >> continual stream of messages such as this:
>> >>
>> >> 2016-08-04 13:05:28.705 547 INFO rally_ovs.plugins.ovs.scenarios.ovn
>> >> [-]
>> >> bind lport_0996bf_cikzNO to sandbox-172.16.200.24 on
>> >> ovn-farm-node-uat-dal09-compute-325
>> >> 2016-08-04 13:05:28.712 547 INFO paramiko.transport [-] Connected
>> >> (version
>> >> 2.0, client OpenSSH_6.6.1p1)
>> >> 2016-08-04 13:05:28.805 547 INFO paramiko.transport [-] Authentication
>> >> (publickey) successful!
>> >> 2016-08-04T13:05:28Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04 13:05:29.042 547 INFO rally_ovs.plugins.ovs.scenarios.ovn
>> >> [-]
>> >> bind lport_0996bf_tvovcK to sandbox-172.16.200.24 on
>> >> ovn-farm-node-uat-dal09-compute-325
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04 13:05:29.285 547 INFO rally_ovs.plugins.ovs.scenarios.ovn
>> >> [-]
>> >> bind lport_0996bf_HwG7AK to sandbox-172.16.200.24 on
>> >> ovn-farm-node-uat-dal09-compute-325
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04 13:05:29.505 547 INFO rally_ovs.plugins.ovs.scenarios.ovn
>> >> [-]
>> >> bind lport_0996bf_Lqbv92 to sandbox-172.16.200.24 on
>> >> ovn-farm-node-uat-dal09-compute-325
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04 13:05:29.724 547 INFO rally_ovs.plugins.ovs.scenarios.ovn
>> >> [-]
>> >> bind lport_0996bf_6f8uQW to sandbox-172.16.200.24 on
>> >> ovn-farm-node-uat-dal09-compute-325
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04T13:05:29Z|00002|vsctl|WARN|/proc/0/cmdline: open failed (No
>> >> such file or directory)
>> >> 2016-08-04 13:05:29.944 547 INFO rally_ovs.plugins.ovs.scenarios.ovn
>> >> [-]
>> >> bind lport_0996bf_nKl2XF to sandbox-172.16.200.24 on
>> >> ovn-farm-node-uat-dal09-compute-325
>> >>
>> >> Tracing these down, this is due to the check in
>> >> vsctl_parent_process_info(),
>> >> which is verifying if the parent process can be opened. Since
>> >> ovn-scale-test
>> >> runs sandboxes in containers, and these are run as root, there is no
>> >> /proc/0
>> >> in the container. Thus, the check fails, and the error message is
>> >> printed
>> >> out.
>> >> Lowering the log level here results in less logs being dumped for this
>> >> failure
>> >> as ovn-scale-test runs.
>> >>
>> >> [1] https://github.com/openvswitch/ovn-scale-test
>> >> [2]
>> >>
>> >> https://github.com/openvswitch/ovn-scale-test/blob/master/rally_ovs/plugins/ovs/scenarios/ovn.py#L255
>> >>
>> >> Signed-off-by: Kyle Mestery <mestery at mestery.com>
>> >> ---
>> >>  utilities/ovs-vsctl.c | 2 +-
>> >>  1 file changed, 1 insertion(+), 1 deletion(-)
>> >>
>> >> diff --git a/utilities/ovs-vsctl.c b/utilities/ovs-vsctl.c
>> >> index 722dcd9..56f1906 100644
>> >> --- a/utilities/ovs-vsctl.c
>> >> +++ b/utilities/ovs-vsctl.c
>> >> @@ -2483,7 +2483,7 @@ vsctl_parent_process_info(void)
>> >>
>> >>      f = fopen(procfile, "r");
>> >>      if (!f) {
>> >> -        VLOG_WARN("%s: open failed (%s)", procfile,
>> >> ovs_strerror(errno));
>> >> +        VLOG_DBG("%s: open failed (%s)", procfile,
>> >> ovs_strerror(errno));
>> >>          free(procfile);
>> >>          return NULL;
>> >>      }
>> >> --
>> >> 2.7.4 (Apple Git-66)
>> >>
>> >> _______________________________________________
>> >> dev mailing list
>> >> dev at openvswitch.org
>> >> http://openvswitch.org/mailman/listinfo/dev
>> >
>> >
>> > I wonder if we should log it at all if not being able to proc file can
>> > be
>> > expected in real life.
>>
>> I'm fine with that approach as well, I can spin another patch.
>
>
> Thanks, that can useful when proc file system is not available in general.
>
> In addition, I wonder if we should separate the case of parent_pid being
> zero.
> and  may be we can just return a hard coded string,  say "init", since
> /proc/0 does not exist as you have pointed out.
>
Rather than try and deduce something here, I'm just going to remove
the log message. The non-Linux case already simply returns NULL
without logging a warning, so this matches that case as well. New
version inbound.