/// <summary>
/// Assign a container to this node to facilitate
/// <paramref name="request"/>
/// . If node does
/// not have enough memory, create a reservation. This is called once we are
/// sure the particular request should be facilitated by this node.
/// </summary>
/// <param name="node">The node to try placing the container on.</param>
/// <param name="request">The ResourceRequest we're trying to satisfy.</param>
/// <param name="type">The locality of the assignment.</param>
/// <param name="reserved">Whether there's already a container reserved for this app on the node.
/// </param>
/// <returns>
/// If an assignment was made, returns the resources allocated to the
/// container. If a reservation was made, returns
/// FairScheduler.CONTAINER_RESERVED. If no assignment or reservation was
/// made, returns an empty resource.
/// </returns>
private Org.Apache.Hadoop.Yarn.Api.Records.Resource AssignContainer(FSSchedulerNode
node, ResourceRequest request, NodeType type, bool reserved)
{
// How much does this request need?
Org.Apache.Hadoop.Yarn.Api.Records.Resource capability = request.GetCapability();
// How much does the node have?
Org.Apache.Hadoop.Yarn.Api.Records.Resource available = node.GetAvailableResource
();
Container container = null;
if (reserved)
{
container = node.GetReservedContainer().GetContainer();
}
else
{
container = CreateContainer(node, capability, request.GetPriority());
}
// Can we allocate a container on this node?
if (Resources.FitsIn(capability, available))
{
// Inform the application of the new container for this request
RMContainer allocatedContainer = Allocate(type, node, request.GetPriority(), request
, container);
if (allocatedContainer == null)
{
// Did the application need this resource?
if (reserved)
{
Unreserve(request.GetPriority(), node);
}
return(Resources.None());
}
// If we had previously made a reservation, delete it
if (reserved)
{
Unreserve(request.GetPriority(), node);
}
// Inform the node
node.AllocateContainer(allocatedContainer);
// If this container is used to run AM, update the leaf queue's AM usage
if (GetLiveContainers().Count == 1 && !GetUnmanagedAM())
{
((FSLeafQueue)GetQueue()).AddAMResourceUsage(container.GetResource());
SetAmRunning(true);
}
return(container.GetResource());
}
else
{
if (!FairScheduler.FitsInMaxShare(((FSLeafQueue)GetQueue()), capability))
{
return(Resources.None());
}
// The desired container won't fit here, so reserve
Reserve(request.GetPriority(), node, container, reserved);
return(FairScheduler.ContainerReserved);
}
}
/// <summary>
/// Called when this application already has an existing reservation on the
/// given node.
/// </summary>
/// <remarks>
/// Called when this application already has an existing reservation on the
/// given node. Sees whether we can turn the reservation into an allocation.
/// Also checks whether the application needs the reservation anymore, and
/// releases it if not.
/// </remarks>
/// <param name="node">Node that the application has an existing reservation on</param>
public virtual Org.Apache.Hadoop.Yarn.Api.Records.Resource AssignReservedContainer
(FSSchedulerNode node)
{
RMContainer rmContainer = node.GetReservedContainer();
Priority priority = rmContainer.GetReservedPriority();
// Make sure the application still needs requests at this priority
if (GetTotalRequiredResources(priority) == 0)
{
Unreserve(priority, node);
return(Resources.None());
}
// Fail early if the reserved container won't fit.
// Note that we have an assumption here that there's only one container size
// per priority.
if (!Resources.FitsIn(node.GetReservedContainer().GetReservedResource(), node.GetAvailableResource
()))
{
return(Resources.None());
}
return(AssignContainer(node, true));
}