public Sampler(long timeBase, int divisor, int samplerRate, int maxCallstackDepth, int startDelay, int bufferLength = 8192)
{
mTimeBase = timeBase;
mDivisor = divisor;
mSamplerRate = samplerRate;
mMaxCallstackDepth = maxCallstackDepth;
mStartDelay = startDelay;
// allocate buffers
mReadData = new Address[bufferLength];
mData = new Address[bufferLength];
// allocate reusable sample class
mSample = new Protocol.Sampler_sample();
mSample.ticktimes = new _root.Vector <double>();
mSample.callstack = new _root.Vector <uint>();
mSample.callstack.length = (uint)maxCallstackDepth;
mSample.callstack.length = 0;
// save target thread id
mTargetThread = mach_thread_self();
// setup architecture specific settings
var arch = flash.system.Capabilities.cpuArchitecture;
switch (arch)
{
case "ARM":
mThreadStateLength = 17;
mThreadStateFlavor = 1;
mRegisterPC = 15;
mRegisterBP = 7;
break;
case "x86":
mThreadStateLength = 32;
mThreadStateFlavor = 1;
mRegisterPC = 10;
mRegisterBP = 6;
break;
default:
Console.WriteLine("Telemetry: Architecture not supported for sampling");
return;
}
// start sampler thread
mSamplerThread = new Thread(SamplerThreadFunc);
mSamplerThread.Priority = ThreadPriority.Highest;
mSamplerThread.Start();
Console.WriteLine("Telemetry: Sampler started rate: {0} ms", samplerRate);
}
// write sampler data to AMF
public void Write(MethodMap methodMap, bool combineSamples = true)
{
// get accumulated sampler data
Address[] data = GetSamplerData();
// AMF serializable sample to write to
Protocol.Sampler_sample sample = mSample;
int lastCallStackIndex = 0;
int lastCallStackCount = 0;
// process all samples
// this code is tricky because it tries to combine consecutive samples with the exact same callstack
int sampleCount = 0;
int index = 0;
for (;;)
{
// get length of callstack
int count = (int)data[index++];
if (count == 0)
{
break;
}
// get sample time
int time = (int)data[index++];
// compare the last callstack with this one
// if they are equal, the samples can be combined
// else we have to start a new sample
if (!combineSamples || (lastCallStackCount != count) || !ArrayEquals(data, index, lastCallStackIndex, count))
{
// call stack is different...
if (sample.numticks > 0)
{
// write last sample to log
Session.WriteValueImmediate(sNameSamplerSample, sample);
// reset sample for new callstack
sample.numticks = 0;
sample.ticktimes.length = 0;
}
// translate callstack to method ids
var callstack = sample.callstack;
callstack.length = 0;
for (int i = 0; i < count; i++)
{
bool topOfStack;
uint methodId = methodMap.GetMethodId(data[index + i], out topOfStack, true);
// add method id
callstack.push(methodId);
// abort callstack if we are at a "top of stack" method
if (topOfStack)
{
break;
}
}
// save last callstack position
lastCallStackIndex = index;
lastCallStackCount = count;
}
// add tick to sample
sample.numticks++;
sample.time = time;
sample.ticktimes.push((double)time);
// advance to next sample
index += count;
sampleCount++;
}
if (sample.numticks > 0)
{
// write last sample to log
Session.WriteValueImmediate(sNameSamplerSample, sample);
// reset sample for new callstack
sample.numticks = 0;
sample.ticktimes.length = 0;
}
if (sampleCount > 0)
{
// TODO:
Session.WriteValue(".sampler.medianInterval", 1000);
Session.WriteValue(".sampler.averageInterval", 1000);
Session.WriteValue(".sampler.maxInterval", 1000);
}
}
