Sounds like a good addition, Sergey. Please go ahead and create a jira for this and attach a patch whenever you're ready. Note that this is will be for the 3.5 and 3.6 branches. For the 3.4 branch, we pretty much accept only bug fixes at this point, unless the community speaks up and pushes for the change. Since this is for monitoring, it doesn't sound bad to have it in the 3.4 branch too, but I'll let others chime in and say what they prefer.
Also, you mention that you're using this to determine when an instance is about to fail. Could you be more specific? -Flavio > On 02 May 2016, at 14:40, Sergey Maslyakov <[email protected]> wrote: > > I have a patch for the 3.4.x line that adds some simple heap stats into the > "mntr" 4lw response. I use it to monitor the memory utilization by the > service to have an early warning that the instance is about to fail. Would > the community/maintainers be interested in this contribution? If so, I can > open a JIRA issue and then submit a patch with it. Please let me know if > there is interest in this patch. > > This is how the proposed change looks like (see the yellow highlight below): > > [evolvah@vp-backup-1 zookeeper-3.4.8]$ echo mntr | nc localhost 2181 > > zk_version 3.4.8-1740158, built on 04/20/2016 16:14 GMT > > zk_avg_latency 0 > > zk_max_latency 0 > > zk_min_latency 0 > > zk_packets_received 1 > > zk_packets_sent 0 > > zk_num_alive_connections 1 > > zk_outstanding_requests 0 > > zk_server_state standalone > > zk_znode_count 4 > > zk_watch_count 0 > > zk_ephemerals_count 0 > > zk_approximate_data_size 27 > > zk_max_memory 894959616 > > zk_total_memory 60293120 > > zk_free_memory 50368208 > > zk_open_file_descriptor_count 25 > > zk_max_file_descriptor_count 1048576
