I support the effort, Armand. On Wed, Oct 4, 2017 at 3:59 PM, Armand Grillet <agril...@mesosphere.io> wrote:
> Hi all, > > We currently use three levels of verbose logging via the VLOG macro. I > propose to add two levels and change how we use the current ones to make > debugging easier for Mesos developers. > > The current situation is: > > - VLOG(1) is used for Mesos and libprocess events such as the > admission of an agent by a master. It is also used for a few Mesos > common > events, e.g. the allocation of resources on an agent. > - VLOG(2) is used for Mesos and libprocess common events, e.g. the > reception of an offer by a Mesos scheduler. > - VLOG(3) is used when a Mesos scheduler process saves the PID > associated with each slave and for libprocess events related to timers, > clocks, and waiter processes. > > As an example, running GLOG_v=<level> ./mesos-tests --gtest_filter=" > OversubscriptionTest.UpdateAllocatorOnSchedulerFailover" --verbose > returns: > > - 212 lines of logs with level = 1. > - 695 lines of logs with level = 2. > - 782 lines of logs with level = 3. > > The logs at level 2 are quite noisy. This is mainly due to the number of > messages regarding libprocess recurring events such as process resumptions: > https://github.com/apache/mesos/blob/d863620e5cb82b7f22cade0da0a0d1 > 8afbdf9136/3rdparty/libprocess/src/process.cpp#L3245 > > To improve the situation, I suggest having five levels: > > - VLOG(1), used for Mesos events. > - VLOG(2), used for Mesos common/recurring events. > - VLOG(3), used for libprocess events. > - VLOG(4), used for libprocess common/recurring events. > - VLOG(5), used for libprocess events related to timers, clocks, and > waiter processes. > > This change would allow us to read the Mesos verbose logs without having to > see the ones concerning libprocess, a use case that seems reasonable for > Mesos developers. The new log levels would make it possible to have the > same logs as before when necessary. > > What do you think about this? Please feel free to share your thoughts and > comments. > > -- > Armand Grillet > Software Engineer, Mesosphere >
