[ 
https://issues.apache.org/jira/browse/HTRACE-214?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14659485#comment-14659485
 ] 

Masatake Iwasaki commented on HTRACE-214:
-----------------------------------------

So {{TracerPool#loadReceiverType}} (via TracerBuilder) is high-level API 
keeping single receiver instance per type and users can override the guard by 
using {{TracerPool#addReceiver}} if it is really necessary. We could add usage 
and Javadoc about this too in follow-up documentation work.

bq. I'm nearly done porting Hadoop to the new API, will post a github branch 
when I complete it...

Thanks! I'm not sure about how should I pass around already created Tracer 
instance in tracee process. It will show me examples.


> De-globalize Tracer.java
> ------------------------
>
>                 Key: HTRACE-214
>                 URL: https://issues.apache.org/jira/browse/HTRACE-214
>             Project: HTrace
>          Issue Type: Sub-task
>    Affects Versions: 4.0
>            Reporter: Colin Patrick McCabe
>            Assignee: Colin Patrick McCabe
>         Attachments: HTRACE-214.001.patch, HTRACE-214.002.patch, 
> HTRACE-214.003.patch, HTRACE-214.004.patch
>
>
> De-globalize Tracer.java.
> Currently, Tracer is a Singleton managed by TracerHolder.  Instead, Tracer 
> objects should be created by each process or library that needs to use 
> HTrace.  This enables a few things:
> * When the Tracer object is created, we can give it a name.  Then we can use 
> this name in the "process id" of all spans created by that tracer, rather 
> than trying to scrape the JVM name using "questionable" methods.
> * SpanReceivers can be shared between multiple Tracer objects in the same 
> process.  The span receivers are reference counted.  This should eliminate 
> the "double tracing" issues we have had when tracing client libraries inside 
> processes which also want tracing.
> * Tracers can be closed by calling Tracer#close.  If the Tracer being closed 
> is the last tracer in the process, it will close all the span receivers.
> * We will have a TracerFactory that takes care of the details of creating the 
> right span receivers based on the configuration.  This removes some 
> boilerplate that is currently needed to enable HTrace in an application or 
> library.  We can also make SpanReceiverFactory package-private since it will 
> no longer need to be publicly visible.



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

Reply via email to