public virtual int Compare(Schedulable s1, Schedulable s2)
{
ResourceWeights sharesOfCluster1 = new ResourceWeights();
ResourceWeights sharesOfCluster2 = new ResourceWeights();
ResourceWeights sharesOfMinShare1 = new ResourceWeights();
ResourceWeights sharesOfMinShare2 = new ResourceWeights();
ResourceType[] resourceOrder1 = new ResourceType[NumResources];
ResourceType[] resourceOrder2 = new ResourceType[NumResources];
// Calculate shares of the cluster for each resource both schedulables.
CalculateShares(s1.GetResourceUsage(), clusterCapacity, sharesOfCluster1, resourceOrder1
, s1.GetWeights());
CalculateShares(s1.GetResourceUsage(), s1.GetMinShare(), sharesOfMinShare1, null,
ResourceWeights.Neutral);
CalculateShares(s2.GetResourceUsage(), clusterCapacity, sharesOfCluster2, resourceOrder2
, s2.GetWeights());
CalculateShares(s2.GetResourceUsage(), s2.GetMinShare(), sharesOfMinShare2, null,
ResourceWeights.Neutral);
// A queue is needy for its min share if its dominant resource
// (with respect to the cluster capacity) is below its configured min share
// for that resource
bool s1Needy = sharesOfMinShare1.GetWeight(resourceOrder1[0]) < 1.0f;
bool s2Needy = sharesOfMinShare2.GetWeight(resourceOrder2[0]) < 1.0f;
int res = 0;
if (!s2Needy && !s1Needy)
{
res = CompareShares(sharesOfCluster1, sharesOfCluster2, resourceOrder1, resourceOrder2
);
}
else
{
if (s1Needy && !s2Needy)
{
res = -1;
}
else
{
if (s2Needy && !s1Needy)
{
res = 1;
}
else
{
// both are needy below min share
res = CompareShares(sharesOfMinShare1, sharesOfMinShare2, resourceOrder1, resourceOrder2
);
}
}
}
if (res == 0)
{
// Apps are tied in fairness ratio. Break the tie by submit time.
res = (int)(s1.GetStartTime() - s2.GetStartTime());
}
return(res);
}
public virtual void TestCalculateShares()
{
Org.Apache.Hadoop.Yarn.Api.Records.Resource used = Resources.CreateResource(10, 5
);
Org.Apache.Hadoop.Yarn.Api.Records.Resource capacity = Resources.CreateResource(100
, 10);
ResourceType[] resourceOrder = new ResourceType[2];
ResourceWeights shares = new ResourceWeights();
DominantResourceFairnessPolicy.DominantResourceFairnessComparator comparator = new
DominantResourceFairnessPolicy.DominantResourceFairnessComparator();
comparator.CalculateShares(used, capacity, shares, resourceOrder, ResourceWeights
.Neutral);
NUnit.Framework.Assert.AreEqual(.1, shares.GetWeight(ResourceType.Memory), .00001
);
NUnit.Framework.Assert.AreEqual(.5, shares.GetWeight(ResourceType.Cpu), .00001);
NUnit.Framework.Assert.AreEqual(ResourceType.Cpu, resourceOrder[0]);
NUnit.Framework.Assert.AreEqual(ResourceType.Memory, resourceOrder[1]);
}
private int CompareShares(ResourceWeights shares1, ResourceWeights shares2, ResourceType
[] resourceOrder1, ResourceType[] resourceOrder2)
{
for (int i = 0; i < resourceOrder1.Length; i++)
{
int ret = (int)Math.Signum(shares1.GetWeight(resourceOrder1[i]) - shares2.GetWeight
(resourceOrder2[i]));
if (ret != 0)
{
return(ret);
}
}
return(0);
}
/// <summary>Calculates and orders a resource's share of a pool in terms of two vectors.
/// </summary>
/// <remarks>
/// Calculates and orders a resource's share of a pool in terms of two vectors.
/// The shares vector contains, for each resource, the fraction of the pool that
/// it takes up. The resourceOrder vector contains an ordering of resources
/// by largest share. So if resource=<10 MB, 5 CPU>, and pool=<100 MB, 10 CPU>,
/// shares will be [.1, .5] and resourceOrder will be [CPU, MEMORY].
/// </remarks>
internal virtual void CalculateShares(Org.Apache.Hadoop.Yarn.Api.Records.Resource
resource, Org.Apache.Hadoop.Yarn.Api.Records.Resource pool, ResourceWeights shares
, ResourceType[] resourceOrder, ResourceWeights weights)
{
shares.SetWeight(ResourceType.Memory, (float)resource.GetMemory() / (pool.GetMemory
() * weights.GetWeight(ResourceType.Memory)));
shares.SetWeight(ResourceType.Cpu, (float)resource.GetVirtualCores() / (pool.GetVirtualCores
() * weights.GetWeight(ResourceType.Cpu)));
// sort order vector by resource share
if (resourceOrder != null)
{
if (shares.GetWeight(ResourceType.Memory) > shares.GetWeight(ResourceType.Cpu))
{
resourceOrder[0] = ResourceType.Memory;
resourceOrder[1] = ResourceType.Cpu;
}
else
{
resourceOrder[0] = ResourceType.Cpu;
resourceOrder[1] = ResourceType.Memory;
}
}
}
