/// <summary>Checks whether a block is sufficiently replicated for decommissioning.</summary>
/// <remarks>
/// Checks whether a block is sufficiently replicated for decommissioning.
/// Full-strength replication is not always necessary, hence "sufficient".
/// </remarks>
/// <returns>true if sufficient, else false.</returns>
private bool IsSufficientlyReplicated(BlockInfoContiguous block, BlockCollection
bc, NumberReplicas numberReplicas)
{
int numExpected = bc.GetBlockReplication();
int numLive = numberReplicas.LiveReplicas();
if (!blockManager.IsNeededReplication(block, numExpected, numLive))
{
// Block doesn't need replication. Skip.
Log.Trace("Block {} does not need replication.", block);
return(true);
}
// Block is under-replicated
Log.Trace("Block {} numExpected={}, numLive={}", block, numExpected, numLive);
if (numExpected > numLive)
{
if (bc.IsUnderConstruction() && block.Equals(bc.GetLastBlock()))
{
// Can decom a UC block as long as there will still be minReplicas
if (numLive >= blockManager.minReplication)
{
Log.Trace("UC block {} sufficiently-replicated since numLive ({}) " + ">= minR ({})"
, block, numLive, blockManager.minReplication);
return(true);
}
else
{
Log.Trace("UC block {} insufficiently-replicated since numLive " + "({}) < minR ({})"
, block, numLive, blockManager.minReplication);
}
}
else
{
// Can decom a non-UC as long as the default replication is met
if (numLive >= blockManager.defaultReplication)
{
return(true);
}
}
}
return(false);
}