[ 
https://issues.apache.org/jira/browse/METRON-590?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15749585#comment-15749585
 ] 

ASF GitHub Bot commented on METRON-590:
---------------------------------------

Github user nickwallen commented on a diff in the pull request:

    https://github.com/apache/incubator-metron/pull/395#discussion_r92496235
  
    --- Diff: 
metron-analytics/metron-profiler/src/main/config/profiler.properties ---
    @@ -18,21 +18,44 @@
     #
     #
     
    -##### Storm #####
    +##### Profiler #####
     
    -profiler.workers=1
    -profiler.executors=0
    +# topic from which the profiler consumes messages
     profiler.input.topic=indexing
    +
    +# how frequently the profiler summarizes data - aka duration of each 
profile period
     profiler.period.duration=15
     profiler.period.duration.units=MINUTES
    +
    +# lifespan of a profile - must be greater than twice the profile period
    +# intermediate state may be lost if no messages received within this time 
span
     profiler.ttl=30
     profiler.ttl.units=MINUTES
    -profiler.hbase.salt.divisor=1000
    +
    +# event time processing - the name of the field containing the event 
timestamp
    +profiler.event.timestamp.field=timestamp
    +
    +# event time processing - how long time lags behind the last seen timestamp
    +profiler.event.time.lag=1
    --- End diff --
    
    Yep, good catch


> Enable Use of Event Time in Profiler
> ------------------------------------
>
>                 Key: METRON-590
>                 URL: https://issues.apache.org/jira/browse/METRON-590
>             Project: Metron
>          Issue Type: Improvement
>            Reporter: Nick Allen
>            Assignee: Nick Allen
>
> There are at least two different times that are important to consider when 
> handling the telemetry messages received by Metron.  
> (1) Processing time is the time at which Metron processed the message.  
> (2) Event time is the time at which the event actually occurred.
> If Metron is consuming live data and all is well, the processing and event 
> times may remain close and consistent. When processing time differs from 
> event time the data produced by the Profiler may be inaccurate.  There are a 
> few scenarios under which these times might differ greatly which would 
> negatively impact the feature set produced by the Profiler.  
> (1) When the system has experienced an outage, for example, a scheduled 
> maintenance window. When restarted a high volume of messages will need to be 
> processed by the Profiler.  The output of the Profiler will indicate an 
> increase in activity, although no change in activity actually occurred on the 
> target network.  This could happen whether the outage was Metron itself or an 
> upstream system that feeds data to Metron.
> (2) If the user attempts to replay historical telemetry through the Profiler, 
> the Profiler will attribute the activity to the time period in which it was 
> processed.  Obviously the activity should be attributed to the time period in 
> which the raw telemetry events originated in.
> There are some scenarios when processing time might be preferred and other 
> use cases where event time is preferred.  The Profiler should be enhanced to 
> allow it to produce profiles based on either processing time or event time.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to