hadoop-yarn-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Chris Douglas (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (YARN-2475) ReservationSystem: replan upon capacity reduction
Date Wed, 10 Sep 2014 20:30:35 GMT

    [ https://issues.apache.org/jira/browse/YARN-2475?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14129041#comment-14129041
] 

Chris Douglas commented on YARN-2475:
-------------------------------------

{{SimpleCapacityReplanner}}
* The Clock can be initialized in the constructor, declared private and final
* The exception refers to an InventorySizeAdjusmentPolicy
* nit: redundant parenthesis in the main loop, exceeds 80 char
* {{curSessions}} cannot be null; prefer {{!isEmpty()}} to {{size() > 0}}
** Is this check even necessary? {{sort}} and the following loop should be noops
* A brief comment about the natural order of {{ReservationAllocations}} would help readability
of this loop. It's in the class doc, but something inline would be helpful
* An internal {{Resource(0,0)}} could be reused, instead of creating it in the loop
* Could the inner loop be more readable? The embedded function calls in the {{Resource}} arithmetic
are hard to read (pseudo):
{code}
ArrayList<> curSessions = new ArrayList<>(plan.getResourcesAtTime(t));
Collections.sort(curSessions);
for (Iterator<> i = curSessions.iterator(); i.hasNext() && excessCap > 0;)
{
  InMemoryReservationAllocation a = (InMemoryReservationAllocation) i.next();
  plan.deleteReservation(a.getReservationId());
  excessCap -= a.getResourcesAtTime(t);
}
{code}
* Why is the enforcement window tied to {{CapacitySchedulerConfiguration}}?

{{TestSimpleCapacityReplanner}}
* Tests should not call {{Thread.sleep}}; instead update the mock
* Passing in a mocked {{Clock}} to the cstr rather than assigning it in the test is cleaner
* Instead of {{assertTrue(cond != null)}} use {{assertNotNull(cond)}} (same for positive null
check)
* The test should not catch and discard {{PlanningException}}

> ReservationSystem: replan upon capacity reduction
> -------------------------------------------------
>
>                 Key: YARN-2475
>                 URL: https://issues.apache.org/jira/browse/YARN-2475
>             Project: Hadoop YARN
>          Issue Type: Sub-task
>          Components: resourcemanager
>            Reporter: Carlo Curino
>            Assignee: Carlo Curino
>         Attachments: YARN-2475.patch
>
>
> In the context of YARN-1051, if capacity of the cluster drops significantly upon machine
failures we need to trigger a reorganization of the planned reservations. As reservations
are "absolute" it is possible that they will not all fit, and some need to be rejected a-posteriori.
 



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

Mime
View raw message