protected TimeSpan ComputeNewTimeOut(double ms, TimeStats stats, double min, double stdevs)
{
stats.AddSample(ms);
double timeout = stats.Average + stdevs * stats.StdDev;
timeout = Math.Max(min, timeout);
return(TimeSpan.FromMilliseconds(timeout));
}
public TimeStats Clone()
{
var ret = new TimeStats(_exp_moving_rtt, _exp_factor);
ret._exp_moving_square_rtt = _exp_moving_square_rtt;
ret._exp_moving_stdev = _exp_moving_stdev;
ret._max_rtt = _max_rtt;
return(ret);
}
private string ToCSVString()
{
string csv = "Name, " + TimeStats.GetCSVHeader();
foreach (string key in timeDictionary.Keys)
{
csv += key + ", " + timeDictionary[key].ToCSVString();
}
return(csv);
}
public void StartMeasuring(string name)
{
TimeStats stats = new TimeStats();
if (timeDictionary.ContainsKey(name))
{
timeDictionary[name] = stats;
}
else
{
timeDictionary.Add(name, stats);
}
}
public ReqrepManager(object info, PType prefix)
{
ReqrepManager existing;
lock ( _inst_tab_sync ) {
if (_instance_table.TryGetValue(info, out existing))
{
throw new Exception("Already an existing ReqrepManager for: " + info.ToString());
}
else
{
_instance_table[info] = this;
}
}
_info = info.ToString();
_prefix = prefix;
_req_handler_table = new Hashtable();
Random r = new Random();
//Don't use negative numbers:
_req_state_table = new UidGenerator <RequestState>(r, true);
//Don't use negative numbers:
_reply_id_table = new UidGenerator <ReplyState>(r, true);
_rep_handler_table = new Hashtable();
/**
* We keep a list of the most recent 1000 replies until they
* get too old. If the reply gets older than reptimeout, we
* remove it
*/
_reply_cache = new Cache(1000);
_reply_cache.EvictionEvent += HandleReplyCacheEviction;
/*
* Here we set the timeout mechanisms. There is a default
* value, but this is now dynamic based on the observed
* RTT of the network
*/
//resend the request after 5 seconds.
_edge_reqtimeout = new TimeSpan(0, 0, 0, 0, 5000);
_nonedge_reqtimeout = new TimeSpan(0, 0, 0, 0, 5000);
//Start with 50 sec timeout
_acked_reqtimeout = new TimeSpan(0, 0, 0, 0, 50000);
//Here we track the statistics to improve the timeouts:
_nonedge_rtt_stats = new TimeStats(_nonedge_reqtimeout.TotalMilliseconds, 0.98);
_edge_rtt_stats = new TimeStats(_edge_reqtimeout.TotalMilliseconds, 0.98);
_acked_rtt_stats = new TimeStats(_acked_reqtimeout.TotalMilliseconds, 0.98);
_last_check = DateTime.UtcNow;
}
public TimeOutManager()
{
/*
* Here we set the timeout mechanisms. There is a default
* value, but this is now dynamic based on the observed
* RTT of the network
*/
//resend the request after 5 seconds by default
_min_timeout = 5000;
_global_stats = new TimeStats(_min_timeout, 0.98);
//Start with 50 sec timeout
_acked_rtt_stats = new TimeStats(_min_timeout * 10, 0.98);
_last_check = DateTime.UtcNow;
_send_stats = new Cache(1000);
_type_stats = new Cache(100);
_sync = new object();
}
public void AddReplySampleFor(RequestState reqs, ISender s, TimeSpan rtt)
{
/*
* Let's look at how long it took to get this reply:
*/
if (reqs.GotAck)
{
lock (_sync) {
TimeStats ts = _acked_rtt_stats;
ts.AddSample(rtt.TotalMilliseconds);
_min_timeout = Math.Min(_min_timeout, ts.AvePlusKStdDev(_STD_DEVS));
}
}
else
{
AddAckSampleFor(reqs, s, rtt);
}
}
private Pair <TimeStats, TimeStats> GetStatsFor(ISender s)
{
System.Type st = s.GetType();
TimeStats typets = (TimeStats)_type_stats[st];
if (null == typets)
{
typets = _global_stats.Clone();
_type_stats[st] = typets;
}
TimeStats sendts = (TimeStats)_send_stats[s];
if (null == sendts)
{
sendts = typets.Clone();
_send_stats[s] = sendts;
}
return(new Pair <TimeStats, TimeStats>(typets, sendts));
}
public TimeStats Clone() {
var ret = new TimeStats(_exp_moving_rtt, _exp_factor);
ret._exp_moving_square_rtt = _exp_moving_square_rtt;
ret._exp_moving_stdev = _exp_moving_stdev;
ret._max_rtt = _max_rtt;
return ret;
}
public TimeOutManager() {
/*
* Here we set the timeout mechanisms. There is a default
* value, but this is now dynamic based on the observed
* RTT of the network
*/
//resend the request after 5 seconds by default
_min_timeout = 5000;
_global_stats = new TimeStats(_min_timeout, 0.98);
//Start with 50 sec timeout
_acked_rtt_stats = new TimeStats(_min_timeout * 10, 0.98);
_last_check = DateTime.UtcNow;
_send_stats = new Cache(1000);
_type_stats = new Cache(100);
_sync = new object();
}
protected TimeSpan ComputeNewTimeOut(double ms, TimeStats stats, double min, double stdevs) {
stats.AddSample(ms);
double timeout = stats.Average + stdevs * stats.StdDev;
timeout = Math.Max(min, timeout);
return TimeSpan.FromMilliseconds( timeout );
}
/**
* Protected constructor, we want to control ReqrepManager instances
* running on a node.
* @param node The Node we work for
*/
public ReqrepManager(string info) {
_info = info;
_rand = new Random();
_req_handler_table = new Hashtable();
_req_state_table = new Hashtable();
_rep_handler_table = new Hashtable();
/**
* We keep a list of the most recent 1000 replies until they
* get too old. If the reply gets older than reptimeout, we
* remove it
*/
_reply_cache = new Cache(1000);
/*
* Here we set the timeout mechanisms. There is a default
* value, but this is now dynamic based on the observed
* RTT of the network
*/
//resend the request after 5 seconds.
_edge_reqtimeout = new TimeSpan(0,0,0,0,5000);
_nonedge_reqtimeout = new TimeSpan(0,0,0,0,5000);
//Start with 50 sec timeout
_acked_reqtimeout = new TimeSpan(0,0,0,0,50000);
//Here we track the statistics to improve the timeouts:
_nonedge_rtt_stats = new TimeStats(_nonedge_reqtimeout.TotalMilliseconds, 0.98);
_edge_rtt_stats = new TimeStats(_edge_reqtimeout.TotalMilliseconds, 0.98);
_acked_rtt_stats = new TimeStats(_acked_reqtimeout.TotalMilliseconds, 0.98);
_last_check = DateTime.UtcNow;
}
public ReqrepManager(string info, PType prefix) {
lock( _inst_tab_sync ) {
_instance_table.Replace(info, this);
}
_info = info;
_prefix = prefix;
_req_handler_table = new Hashtable();
Random r = new Random();
//Don't use negative numbers:
_req_state_table = new UidGenerator<RequestState>(r, true);
//Don't use negative numbers:
_reply_id_table = new UidGenerator<ReplyState>(r, true);
_rep_handler_table = new Hashtable();
/**
* We keep a list of the most recent 1000 replies until they
* get too old. If the reply gets older than reptimeout, we
* remove it
*/
_reply_cache = new Cache(1000);
_reply_cache.EvictionEvent += HandleReplyCacheEviction;
/*
* Here we set the timeout mechanisms. There is a default
* value, but this is now dynamic based on the observed
* RTT of the network
*/
//resend the request after 5 seconds.
_edge_reqtimeout = new TimeSpan(0,0,0,0,5000);
_nonedge_reqtimeout = new TimeSpan(0,0,0,0,5000);
//Start with 50 sec timeout
_acked_reqtimeout = new TimeSpan(0,0,0,0,50000);
//Here we track the statistics to improve the timeouts:
_nonedge_rtt_stats = new TimeStats(_nonedge_reqtimeout.TotalMilliseconds, 0.98);
_edge_rtt_stats = new TimeStats(_edge_reqtimeout.TotalMilliseconds, 0.98);
_acked_rtt_stats = new TimeStats(_acked_reqtimeout.TotalMilliseconds, 0.98);
_last_check = DateTime.UtcNow;
}
void RunLoop()
{
Log.Info(Strings.Device_Polling_Loop_Started);
var stream = DeviceStream;
var cancel = Cancellation.Token;
var responseWaitInterval = TimeSpan.FromMilliseconds(PollingInterval.TotalMilliseconds * 0.9);
var responseBuffer = new byte[stream.MaxResponseSize];
var timeStats = new TimeStats();
uint failedAttemptsCount = 0;
while (!cancel.IsCancellationRequested && failedAttemptsCount < MaxReadAttempts)
{
try
{
timeStats.BeginSample();
// Send request
stream.Write(RequestBytes, 0, RequestBytes.Length);
// Receive response
bool succeed = stream.Read(responseBuffer, 0, responseBuffer.Length, responseWaitInterval, cancel);
var timeElapsed = timeStats.EndSample();
// Log failed attempts
if (!succeed)
{
++failedAttemptsCount;
continue;
}
// Dispatch response
EnqueueEvent(DataReceived, new DataSampleArgs(SampleParse(DateTimeOffset.Now, responseBuffer)));
failedAttemptsCount = 0;
// Wait before next request if needed
if (timeElapsed < PollingInterval)
{
cancel.WaitHandle.WaitOne(PollingInterval - timeElapsed);
Debug.WriteLine("Device polling waited {0:c}", PollingInterval - timeElapsed);
}
}
catch (OperationCanceledException)
{
// This must be caused by StopPolling() and/or Dispose() call
Contract.Assert(cancel.IsCancellationRequested);
break;
}
catch (ObjectDisposedException)
{
// This must be caused by StopPolling() and/or Dispose() call
Contract.Assert(cancel.IsCancellationRequested);
break;
}
catch (Exception exception)
{
Log.ExceptionError(exception, Errors.Data_Request_Failed);
break;
}
}
// Stopped after MaxReadAttempts consequent failed requests
if (MaxReadAttempts == failedAttemptsCount)
{
Log.WarningFormat(Errors.Too_Many_Failed_Attempts_1, failedAttemptsCount, responseWaitInterval);
}
// Notify of this Stop event
Log.Info(Strings.Device_Polling_Loop_Stopped);
// Log time stats if needed
if (timeStats.Avg > PollingInterval)
{
Log.Warning(
string.Concat(
string.Format(Strings.Device_Too_Slow_0, PollingInterval),
Environment.NewLine,
timeStats.ToString(Environment.NewLine, "g")
)
);
}
// Final cleanup
Dispose();
}
