Author: chobrian
Date: Tue Aug 11 08:46:24 2015
New Revision: 1695227
URL: http://svn.apache.org/r1695227
Log:
[REEF-444] Replace Activity with Task on
http://reef.incubator.apache.org/introduction.html
Modified:
incubator/reef/site/introduction.html
incubator/reef/site/reef-architecture.png
incubator/reef/site/states-horizontal.png
Modified: incubator/reef/site/introduction.html
URL:
http://svn.apache.org/viewvc/incubator/reef/site/introduction.html?rev=1695227&r1=1695226&r2=1695227&view=diff
==============================================================================
--- incubator/reef/site/introduction.html (original)
+++ incubator/reef/site/introduction.html Tue Aug 11 08:46:24 2015
@@ -1,13 +1,13 @@
<!DOCTYPE html>
<!--
- | Generated by Apache Maven Doxia at 2015-07-28
+ | Generated by Apache Maven Doxia at 2015-08-11
| Rendered using Apache Maven Fluido Skin 1.4
-->
<html xmlns="http://www.w3.org/1999/xhtml"; xml:lang="en" lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
- <meta name="Date-Revision-yyyymmdd" content="20150728" />
+ <meta name="Date-Revision-yyyymmdd" content="20150811" />
<meta http-equiv="Content-Language" content="en" />
<title>Apache REEF - Introduction to REEF</title>
<link rel="stylesheet" href="./css/apache-maven-fluido-1.4.min.css" />
@@ -434,7 +434,7 @@ under the License. --><h1>Introduction t
<p><i>A running REEF job with two <tt>RunningEvaluators</tt> and one
<tt>RunningTask</tt></i></p>
<p><br /></br></p>
-<p>The above figure presents the REEF components in terms of a running
application, which is written in terms of a <tt>Driver</tt> and task-specific
<tt>Task</tt> modules. The application code is packaged and submitted to a REEF
client API, which in turn submits a REEF-AM configuration to YARN. The REEF-AM
contains a runtime for launching the <tt>Driver</tt> and client libraries for
requesting Evaluators and launching <tt>Activities</tt>. When a request for
<tt>Evaluators</tt> is made, the REEF-AM negotiates containers with the YARN-RM
and launches an <tt>Evaluator</tt> runtime on the YARN-NM that hosts the
allocated container. In turn, the <tt>Driver</tt> is given an
<tt>Evaluator</tt> object reference, which it uses to submit an <tt>Task</tt>.
The <tt>Driver</tt> is also given a <tt>Task</tt> object reference, which it
may use to send messages to the <tt>Task</tt> running in the
<tt>Evaluator</tt>. The REEF layer implements these communication channels and
encodes the computationa
l life-cycle as state transitions, which are surfaced to the <tt>Driver</tt>
in the form of Rx messages.</p>
+<p>The above figure presents the REEF components in terms of a running
application, which is written in terms of a <tt>Driver</tt> and task-specific
<tt>Task</tt> modules. The application code is packaged and submitted to a REEF
client API, which in turn submits a REEF-AM configuration to YARN. The REEF-AM
contains a runtime for launching the <tt>Driver</tt> and client libraries for
requesting <tt>Evaluators</tt> and launching <tt>Tasks</tt>. When a request for
<tt>Evaluators</tt> is made, the REEF-AM negotiates containers with the YARN-RM
and launches an <tt>Evaluator</tt> runtime on the YARN-NM that hosts the
allocated container. In turn, the <tt>Driver</tt> is given an
<tt>Evaluator</tt> object reference, which it uses to submit an <tt>Task</tt>.
The <tt>Driver</tt> is also given a <tt>Task</tt> object reference, which it
may use to send messages to the <tt>Task</tt> running in the
<tt>Evaluator</tt>. The REEF layer implements these communication channels and
encodes the computat
ional life-cycle as state transitions, which are surfaced to the
<tt>Driver</tt> in the form of Rx messages.</p>
<div class="section">
<div class="section">
<h3>Computational Life-Cycle<a name="Computational_Life-Cycle"></a></h3>
@@ -442,13 +442,13 @@ under the License. --><h1>Introduction t
<img src="states-horizontal.png" alt="" /></img>
-<p><i>States of <tt>Evaluator</tt>, <tt>Contexts</tt>, and
<tt>Activities</tt></i></p>
+<p><i>States of <tt>Evaluator</tt>, <tt>Contexts</tt>, and
<tt>Tasks</tt></i></p>
<p><br /></br></p>
-<p>The Figure above describes the state transitions for (a) <tt>Evaluator</tt>
and <tt>Context</tt> and (b) <tt>Task</tt> components. Each state transition is
associated with an object reference that is surfaced to the <tt>Driver</tt> in
an Rx-style interface. For instance, when the YARN-RM notifies the REEF-AM of
an allocated container, the <tt>Driver</tt> is given an
<tt>AllocatedEvaluator</tt> object; containing methods for adding
configurations (i.e., for data services, see below) and file resources, and
submit methods that bootstraps the <tt>Evaluator</tt> runtime on the YARN-NM.
When an <tt>Evaluator</tt> bootstrap successfully completes, the
<tt>Driver</tt> is given an <tt>ActiveContext</tt> object, which can be used to
launch <tt>Activities</tt> or to initiate a close, which triggers a shutdown
event at the <tt>Evaluator</tt> runtime and a subsequent container release at
the YARN-RM. If at any point a failure occurs, the <tt>Driver</tt> is passed a
<tt>FailedEvaluator</tt> o
bject; containing an exception trace when possible.</p>
-<p>Recall that the <tt>Driver</tt> launches a <tt>Task</tt> on a submit method
call from the <tt>ActiveContext</tt> reference. This state transition is
denoted in the Figure above by the edge labeled submit; spanning the two state
machines. The REEF-AM passes a <tt>RunningActivity</tt> object to the
<tt>Driver</tt> after receiving confirmation of a successful <tt>Task</tt>
start or resume. The <tt>Driver</tt> may use the <tt>RunningActivity</tt>
reference to close or suspend the execution; triggering a
<tt>CompletedActivity</tt> or <tt>SuspendedActivity</tt> object reference to
the <tt>Driver</tt>. The <tt>SuspendedActivity</tt> object contains a memento
used to resume the execution on some (possibly alternative)
<tt>ActiveContext</tt>. Exceptions during the <tt>Task</tt> execution are
surfaced to the <tt>Driver</tt> in the form of a <tt>FailedActivity</tt>, which
contains the actual exception object.</p></div>
+<p>The Figure above describes the state transitions for (a) <tt>Evaluator</tt>
and <tt>Context</tt> and (b) <tt>Task</tt> components. Each state transition is
associated with an object reference that is surfaced to the <tt>Driver</tt> in
an Rx-style interface. For instance, when the YARN-RM notifies the REEF-AM of
an allocated container, the <tt>Driver</tt> is given an
<tt>AllocatedEvaluator</tt> object; containing methods for adding
configurations (i.e., for data services, see below) and file resources, and
submit methods that bootstraps the <tt>Evaluator</tt> runtime on the YARN-NM.
When an <tt>Evaluator</tt> bootstrap successfully completes, the
<tt>Driver</tt> is given an <tt>ActiveContext</tt> object, which can be used to
launch <tt>Tasks</tt> or to initiate a close, which triggers a shutdown event
at the <tt>Evaluator</tt> runtime and a subsequent container release at the
YARN-RM. If at any point a failure occurs, the <tt>Driver</tt> is passed a
<tt>FailedEvaluator</tt> object
; containing an exception trace when possible.</p>
+<p>Recall that the <tt>Driver</tt> launches a <tt>Task</tt> on a submit method
call from the <tt>ActiveContext</tt> reference. This state transition is
denoted in the Figure above by the edge labeled submit; spanning the two state
machines. The REEF-AM passes a <tt>RunningTask</tt> object to the
<tt>Driver</tt> after receiving confirmation of a successful <tt>Task</tt>
start or resume. The <tt>Driver</tt> may use the <tt>RunningTask</tt> reference
to close or suspend the execution; triggering a <tt>CompletedTask</tt> or
<tt>SuspendedTask</tt> object reference to the <tt>Driver</tt>. The
<tt>SuspendedTask</tt> object contains a memento used to resume the execution
on some (possibly alternative) <tt>ActiveContext</tt>. Exceptions during the
<tt>Task</tt> execution are surfaced to the <tt>Driver</tt> in the form of a
<tt>FailedTask</tt>, which contains the actual exception object.</p></div>
<div class="section">
<h3>Task Component<a name="Task_Component"></a></h3>
-<p>A <tt>Task</tt> encapsulates the task work of a job. The client interface
contains a single synchronous call method that takes an optional memento
argument and returns a byte array, which will be packaged with the
<tt>CompletedActivity</tt> object surfaced to the <tt>Driver</tt>. An exception
may be thrown at any point during the call method; returning control back to
the <tt>Evaluator</tt>, which packages the exception and sends it to the
<tt>Driver</tt> where it is surfaced as a <tt>FailedActivity</tt>. The
<tt>Evaluator</tt> periodically performs a heartbeat with the REEF-AM to convey
its status information. A <tt>Task</tt> can optionally implement a method
interface that, when called, returns a (bounded) byte array, which the
<tt>Evaluator</tt> includes in its heartbeat to the REEF-AM and surfaced to the
<tt>Driver</tt>.</p></div></div>
+<p>A <tt>Task</tt> encapsulates the task work of a job. The client interface
contains a single synchronous call method that takes an optional memento
argument and returns a byte array, which will be packaged with the
<tt>CompletedTask</tt> object surfaced to the <tt>Driver</tt>. An exception may
be thrown at any point during the call method; returning control back to the
<tt>Evaluator</tt>, which packages the exception and sends it to the
<tt>Driver</tt> where it is surfaced as a <tt>FailedTask</tt>. The
<tt>Evaluator</tt> periodically performs a heartbeat with the REEF-AM to convey
its status information. A <tt>Task</tt> can optionally implement a method
interface that, when called, returns a (bounded) byte array, which the
<tt>Evaluator</tt> includes in its heartbeat to the REEF-AM and surfaced to the
<tt>Driver</tt>.</p></div></div>
</div>
</div>
</div>
Modified: incubator/reef/site/reef-architecture.png
URL:
http://svn.apache.org/viewvc/incubator/reef/site/reef-architecture.png?rev=1695227&r1=1695226&r2=1695227&view=diff
==============================================================================
Binary files - no diff available.
Modified: incubator/reef/site/states-horizontal.png
URL:
http://svn.apache.org/viewvc/incubator/reef/site/states-horizontal.png?rev=1695227&r1=1695226&r2=1695227&view=diff
==============================================================================
Binary files - no diff available.
