/// <exception cref="System.IO.IOException"/>
public TeraScheduler(string splitFilename, string nodeFilename)
{
slotsPerHost = 4;
// get the hosts
IDictionary <string, TeraScheduler.Host> hostIds = new Dictionary <string, TeraScheduler.Host
>();
foreach (string hostName in ReadFile(nodeFilename))
{
TeraScheduler.Host host = new TeraScheduler.Host(hostName);
hosts.AddItem(host);
hostIds[hostName] = host;
}
// read the blocks
IList <string> splitLines = ReadFile(splitFilename);
splits = new TeraScheduler.Split[splitLines.Count];
remainingSplits = 0;
foreach (string line in splitLines)
{
StringTokenizer itr = new StringTokenizer(line);
TeraScheduler.Split newSplit = new TeraScheduler.Split(itr.NextToken());
splits[remainingSplits++] = newSplit;
while (itr.HasMoreTokens())
{
TeraScheduler.Host host = hostIds[itr.NextToken()];
newSplit.locations.AddItem(host);
host.splits.AddItem(newSplit);
}
}
}
/// <exception cref="System.IO.IOException"/>
public TeraScheduler(FileSplit[] realSplits, Configuration conf)
{
this.realSplits = realSplits;
this.slotsPerHost = conf.GetInt(TTConfig.TtMapSlots, 4);
IDictionary <string, TeraScheduler.Host> hostTable = new Dictionary <string, TeraScheduler.Host
>();
splits = new TeraScheduler.Split[realSplits.Length];
foreach (FileSplit realSplit in realSplits)
{
TeraScheduler.Split split = new TeraScheduler.Split(realSplit.GetPath().ToString(
));
splits[remainingSplits++] = split;
foreach (string hostname in realSplit.GetLocations())
{
TeraScheduler.Host host = hostTable[hostname];
if (host == null)
{
host = new TeraScheduler.Host(hostname);
hostTable[hostname] = host;
hosts.AddItem(host);
}
host.splits.AddItem(split);
split.locations.AddItem(host);
}
}
}
/// <exception cref="System.IO.IOException"/>
internal virtual void Solve()
{
TeraScheduler.Host host = PickBestHost();
while (host != null)
{
PickBestSplits(host);
host = PickBestHost();
}
}
internal virtual void PickBestSplits(TeraScheduler.Host host)
{
int tasksToPick = Math.Min(slotsPerHost, (int)Math.Ceil((double)remainingSplits /
hosts.Count));
TeraScheduler.Split[] best = new TeraScheduler.Split[tasksToPick];
foreach (TeraScheduler.Split cur in host.splits)
{
Log.Debug(" examine: " + cur.filename + " " + cur.locations.Count);
int i = 0;
while (i < tasksToPick && best[i] != null && best[i].locations.Count <= cur.locations
.Count)
{
i += 1;
}
if (i < tasksToPick)
{
for (int j = tasksToPick - 1; j > i; --j)
{
best[j] = best[j - 1];
}
best[i] = cur;
}
}
// for the chosen blocks, remove them from the other locations
for (int i_1 = 0; i_1 < tasksToPick; ++i_1)
{
if (best[i_1] != null)
{
Log.Debug(" best: " + best[i_1].filename);
foreach (TeraScheduler.Host other in best[i_1].locations)
{
other.splits.Remove(best[i_1]);
}
best[i_1].locations.Clear();
best[i_1].locations.AddItem(host);
best[i_1].isAssigned = true;
remainingSplits -= 1;
}
}
// for the non-chosen blocks, remove this host
foreach (TeraScheduler.Split cur_1 in host.splits)
{
if (!cur_1.isAssigned)
{
cur_1.locations.Remove(host);
}
}
}
internal virtual TeraScheduler.Host PickBestHost()
{
TeraScheduler.Host result = null;
int splits = int.MaxValue;
foreach (TeraScheduler.Host host in hosts)
{
if (host.splits.Count < splits)
{
result = host;
splits = host.splits.Count;
}
}
if (result != null)
{
hosts.Remove(result);
Log.Debug("picking " + result);
}
return(result);
}
