 testName = "Seek";
 testDescription = "Seek test performs " + QString::number(SEEKER_SEEKCOUNT) +
   " seeks to random positions on device." +
   " Seek lenght is marked on horizontal axis and seek duration is on vertical axis.";
}

Seeker::~Seeker() {}

void Seeker::TestLoop() {
 // erease previous results
 result.erase();
 
 // initialize random number generator
 RandomGenerator gen;
 
 // seek to drive end
 hddsize last = device->GetSize();
 device->SeekTo(last);
 
 // test SEEKER_SEEKCOUNT seeks
 for(int i = 0; i < SEEKER_SEEKCOUNT; ++i) {
  hddsize next = gen.Get64() % device->GetSize();	// get next position
  
  // make timed seek
  hddtime timediff = device->SeekTo(next);
  
  // count seek length
  uint64_t posdiff;
  if(last > next)
   posdiff = last - next;
  else
   posdiff = next - last;
  
  // set last position for next test
  last = next;
  
  qreal pos = (qreal)posdiff / (qreal)device->GetSize();	// calculate pos relative to drivesize
  qreal time = (qreal)timediff / 1000.0;			// evaluate seek time in miliseconds
  
  result.AddSeek(QPointF(pos, time));	// add seek to results
  
  // count test progress
  result.progress = i * 100 / (SEEKER_SEEKCOUNT - 1);
  
  if(testState == STOPPING) {
   return; 
}

void Seeker::InitScene() {
 // clear ticks
 dataTicks->erase();
}
void Seeker::UpdateScene() {
 // draw new seeks
 while(!result.newseeks.empty()) {
  QPointF seek = result.newseeks.pop();
  
  // mark seek as important if it is close to average
  if(seek.ry() < SEEKER_IMPORTANT * result.avg()) {
   dataTicks->AddTick(seek.y(), seek.x(), true);
  } else {
   dataTicks->AddTick(seek.y(), seek.x(), false);
  }
 }
 
 // draw new reference seeks
 while(!reference.newseeks.empty()) {
  QPointF seek = reference.newseeks.pop();
  
  // mark seek as important if it is close to average
  if(seek.ry() < SEEKER_IMPORTANT * reference.avg()) {
   referenceTicks->AddTick(seek.y(), seek.x(), true);
  } else {
   referenceTicks->AddTick(seek.y(), seek.x(), false);
  }
 }
 
 // update lines
 dataAvgLine->SetValue(result.avg());
 referenceAvgLine->SetValue(reference.avg());
 
 // rescale view
 Rescale();
}

int Seeker::GetProgress() {
 return result.progress;
}

void Seeker::SeekResult::AddSeek(QPointF seek) {
 // count new average seek
 average = ((qreal)seeks.count() * average + seek.y()) / (seeks.count() + 1);
 
 seeks.push_back(seek);		// add seek to result seek list
 newseeks.push_back(seek);	// add sekk to stack used for drawing new results
}

qreal Seeker::SeekResult::avg() {
 return average;
}

void Seeker::SeekResult::erase() {
 seeks.erase(seeks.begin(), seeks.end());
 newseeks.erase(newseeks.begin(), newseeks.end());
 progress = 0.0f;
 average = 0.0f;
}

QDomElement Seeker::WriteResults(QDomDocument &doc) {
 // create main seek element
 QDomElement master = doc.createElement("Seeker");
 master.setAttribute("valid", (GetProgress() == 100)?"yes":"no");
 doc.appendChild(master);
 
 // add values to main element
 if(GetProgress() == 100) for(int i = 0; i < result.seeks.size(); ++i) {
  QDomElement value = doc.createElement("Seek");
  value.setAttribute("length", result.seeks[i].x());
  value.setAttribute("time", result.seeks[i].y());
  master.appendChild(value);
 }
 
 return master;
}

void Seeker::RestoreResults(QDomElement &results, DataSet dataset) {
 SeekResult &result = (dataset == REFERENCE)?this->reference:this->result;
 
 // Locate main seek element
 QDomElement seek = results.firstChildElement("Seeker");
 if(!seek.attribute("valid", "no").compare("no")) {
  return;
 }
 
 // clear results and initialize scene
 result.erase();
 (dataset == REFERENCE)?referenceTicks->erase():dataTicks->erase();
 
 // get list of seeks
 QDomNodeList seeks = seek.elementsByTagName("Seek");
 
 // read result data
 for(int i = 0; i < seeks.size(); ++i) {
  result.AddSeek(
     QPointF(
      seeks.at(i).toElement().attribute("length", "0").toDouble(),
      seeks.at(i).toElement().attribute("time", "0").toDouble()));
 }
 
 // set progress
 result.progress = 100;
 
 // refresh view
 UpdateScene();
}

void Seeker::EraseResults(DataSet dataset) {
 if(dataset == RESULTS) {
  result.erase();
  dataTicks->erase();
 } else {
  reference.erase();
  referenceTicks->erase();
 }
 UpdateScene();
}
Time schedule

If you need something, please consider my free time. The empty space is not actually empty. It is just filled with activities that do not follow fixed schedule.