[GitHub] [incubator-skywalking] mbao commented on issue #2410: What will makes CPM less than the real

[GitBox <gi...@apache.org>]

mbao commented on issue #2410: What will makes CPM less than the real 
URL: https://github.com/apache/incubator-skywalking/issues/2410#issuecomment-477447675
 
 
   > > I see that the DataCarrier in TraceSegmentServiceClient uses BufferStrategy.IF_POSSIBLE, so some segment will lose if there is too many segments to send. So is there other situations in which segment will lose?
   > 
   > No.
   > 
   > > If I change the sampleRate from 1000 to 100, only payload of segment persisting will reduce to 10%, right?
   > 
   > If you are saying client sampling, yes. Also the metric values lose 90%.
   
   I mean sampleRate  for backend .  I think sample_n_per_3_secs is the only parameter for me to change the sample rate in agent client, right?
   What do you mean by metric values? I think CPM value is still the exact value as sampleRate just impacts SegmentSpanListener for segment persistence. 
   > 
   > > How many CPM can one backend server load(Simply 8 cpu), and how can I compute how many backend servers should the cluster include?
   > 
   > Depend on ElasticSearch performance. 8 CPU could reach 5k/s at least.
   
   What about mysql?  I think mysql is not optimized .
   
   Thank you very much.

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services