/// <summary>
/// Initializes a new instance of the <see cref="VowpalWabbitThreadedLearning"/> class.
/// </summary>
/// <param name="settings">Common settings used for vw instances.</param>
public VowpalWabbitThreadedLearning(VowpalWabbitSettings settings)
{
if (settings == null)
{
throw new ArgumentNullException("settings");
}
if (settings.ParallelOptions == null)
{
throw new ArgumentNullException("settings.ParallelOptions must be set");
}
Contract.EndContractBlock();
this.Settings = settings;
if (this.Settings.ParallelOptions.CancellationToken == null)
{
this.Settings.ParallelOptions.CancellationToken = new CancellationToken();
}
switch (this.Settings.ExampleDistribution)
{
case VowpalWabbitExampleDistribution.UniformRandom:
this.exampleDistributor = _ => this.random.Next(this.observers.Length);
break;
case VowpalWabbitExampleDistribution.RoundRobin:
this.exampleDistributor = localExampleCount => (int)(localExampleCount % this.observers.Length);
break;
}
this.exampleCount = 0;
this.syncActions = new ConcurrentList <Action <VowpalWabbit> >();
this.vws = new VowpalWabbit[settings.ParallelOptions.MaxDegreeOfParallelism];
this.actionBlocks = new ActionBlock <Action <VowpalWabbit> > [settings.ParallelOptions.MaxDegreeOfParallelism];
this.observers = new IObserver <Action <VowpalWabbit> > [settings.ParallelOptions.MaxDegreeOfParallelism];
// setup AllReduce chain
// root closure
{
var nodeSettings = (VowpalWabbitSettings)settings.Clone();
nodeSettings.Node = 0;
var vw = this.vws[0] = new VowpalWabbit(nodeSettings);
var actionBlock = this.actionBlocks[0] = new ActionBlock <Action <VowpalWabbit> >(
action => action(vw),
new ExecutionDataflowBlockOptions
{
MaxDegreeOfParallelism = 1,
TaskScheduler = settings.ParallelOptions.TaskScheduler,
CancellationToken = settings.ParallelOptions.CancellationToken,
BoundedCapacity = (int)settings.MaxExampleQueueLengthPerInstance
});
}
for (int i = 1; i < settings.ParallelOptions.MaxDegreeOfParallelism; i++)
{
// closure vars
var nodeSettings = (VowpalWabbitSettings)settings.Clone();
nodeSettings.Root = this.vws[0];
nodeSettings.Node = (uint)i;
var vw = this.vws[i] = new VowpalWabbit(nodeSettings);
var actionBlock = this.actionBlocks[i] = new ActionBlock <Action <VowpalWabbit> >(
action => action(vw),
new ExecutionDataflowBlockOptions
{
MaxDegreeOfParallelism = 1,
TaskScheduler = settings.ParallelOptions.TaskScheduler,
CancellationToken = settings.ParallelOptions.CancellationToken,
BoundedCapacity = (int)settings.MaxExampleQueueLengthPerInstance
});
}
// get observers to allow for blocking calls
this.observers = this.actionBlocks.Select(ab => ab.AsObserver()).ToArray();
this.completionTasks = new Task[settings.ParallelOptions.MaxDegreeOfParallelism];
// root closure
{
var vw = this.vws[0];
this.completionTasks[0] = this.actionBlocks[0].Completion
.ContinueWith(_ =>
{
// perform final AllReduce
vw.EndOfPass();
// execute synchronization actions
foreach (var syncAction in this.syncActions.RemoveAll())
{
syncAction(vw);
}
});
}
for (int i = 1; i < this.vws.Length; i++)
{
// perform final AllReduce
var vw = this.vws[i];
this.completionTasks[i] = this.actionBlocks[i].Completion
.ContinueWith(_ => vw.EndOfPass(), this.Settings.ParallelOptions.CancellationToken);
}
}
internal VowpalWabbitExampleJsonValidator(VowpalWabbitSettings settings)
{
settings = (VowpalWabbitSettings)settings.Clone();
settings.EnableStringExampleGeneration = true;
this.vw = new VowpalWabbit(settings);
}
internal VowpalWabbitExampleJsonValidator(VowpalWabbitSettings settings)
{
settings = (VowpalWabbitSettings)settings.Clone();
settings.EnableStringExampleGeneration = true;
this.vw = new VowpalWabbit(settings);
}
