{

public:

TMessageWrapper(void* buf, Int_t len) : TMessage(buf, len) { ResetBit(kIsOwner); }

~TMessageWrapper() override = default;

{

public:

O2SimDevice() = default;

O2SimDevice(o2::steer::O2MCApplication* vmcapp, TVirtualMC* vmc) : mVMCApp{vmcapp}, mVMC{vmc} {}

/// Default destructor

~O2SimDevice() final

{

FairSystemInfo sysinfo;

o2::utils::ShmManager::Instance().release();

LOG(INFO) << "Shutting down O2SimDevice";

LOG(INFO) << "TIME-STAMP " << mTimer.RealTime() << "\t";

LOG(INFO) << "MEM-STAMP " << sysinfo.GetCurrentMemory() / (1024. * 1024) << " " << sysinfo.GetMaxMemory() << " MB\n";

}

protected:

/// Overloads the InitTask() method of FairMQDevice

void InitTask() final

{

// in the initialization phase we will init the simulation

// NOTE: In a FairMQDevice this is better done here (instead of outside) since

// we have to setup simulation + worker in the same thread (due to many threadlocal variables

// in the simulation) ... at least as long FairMQDevice is not spawning workers on the master thread

initSim(fChannels.at("primary-get").at(0), mSimRun);

// set the vmc and app pointers

mVMC = TVirtualMC::GetMC();

mVMCApp = static_cast<o2::steer::O2MCApplication*>(TVirtualMCApplication::Instance());

lateInit();

}

static void CustomCleanup(void* data, void* hint) { delete static_cast<std::string*>(hint); }

public:

void lateInit()

{

// late init

mVMCApp->initLate();

}

// should go into a helper

// this function queries the sim config data and initializes the SimConfig singleton

// returns true if successful / false if not

static bool querySimConfig(FairMQChannel& channel)

{

auto text = new std::string("configrequest");

std::unique_ptr<FairMQMessage> request(channel.NewMessage(const_cast<char*>(text->c_str()),

text->length(), CustomCleanup, text));

std::unique_ptr<FairMQMessage> reply(channel.NewMessage());

int timeoutinMS = 100000; // wait for 100s max

if (channel.Send(request, timeoutinMS) > 0) {

LOG(INFO) << "Waiting for configuration answer ";

if (channel.Receive(reply, timeoutinMS) > 0) {

LOG(INFO) << "Configuration answer received, containing " << reply->GetSize() << " bytes ";

// the answer is a TMessage containing the simulation Configuration

auto message = std::make_unique<o2::devices::TMessageWrapper>(reply->GetData(), reply->GetSize());

auto config = static_cast<o2::conf::SimConfigData*>(message.get()->ReadObjectAny(message.get()->GetClass()));

if (!config) {

return false;

}

LOG(INFO) << "COMMUNICATED ENGINE " << config->mMCEngine;

auto& conf = o2::conf::SimConfig::Instance();

conf.resetFromConfigData(*config);

FairLogger::GetLogger()->SetLogVerbosityLevel(conf.getLogVerbosity().c_str());

delete config;

} else {

LOG(ERROR) << "No configuration received within " << timeoutinMS << "ms\n";

return false;

}

} else {

LOG(ERROR) << "Could not send configuration request within " << timeoutinMS << "ms\n";

return false;

}

return true;

}

// initializes the simulation classes; queries the configuration on a given channel

static bool initSim(FairMQChannel& channel, std::unique_ptr<FairRunSim>& simptr)

{

if (!querySimConfig(channel)) {

return false;

}

LOG(INFO) << "Setting up the simulation ...";

simptr = std::move(std::unique_ptr<FairRunSim>(o2sim_init(true)));

FairSystemInfo sysinfo;

// to finish initialization (trigger further cross section table building etc) -- which especially

// G4 is doing at the first ProcessRun

// The goal is to have everything setup before we fork

TVirtualMC::GetMC()->ProcessRun(0);

LOG(INFO) << "MEM-STAMP END OF SIM INIT" << sysinfo.GetCurrentMemory() / (1024. * 1024) << " "

<< sysinfo.GetMaxMemory() << " MB\n";

return true;

}

bool Kernel(FairMQChannel& requestchannel, FairMQChannel& dataoutchannel)

{

auto text = new std::string("primrequest");

// create message object with a pointer to the data buffer,

// its size,

// custom deletion function (called when transfer is done),

// and pointer to the object managing the data buffer

FairMQMessagePtr request(requestchannel.NewMessage(const_cast<char*>(text->c_str()), // data

text->length(), // size

CustomCleanup,

text));

FairMQMessagePtr reply(dataoutchannel.NewMessage());

mVMCApp->setSimDataChannel(&dataoutchannel);

LOG(INFO) << "Requesting work ";

int timeoutinMS = 1000000; // wait for 1000s max -- we should have a more robust solution

// this should be mostly driven by the time to setup the particle generator in the server

auto sendcode = requestchannel.Send(request, timeoutinMS);

if (sendcode > 0) {

LOG(INFO) << "Waiting for answer ";

// asking for primary generation

int trial = 0;

int code = -1;

do {

code = requestchannel.Receive(reply, timeoutinMS);

trial++;

if (code > 0) {

LOG(INFO) << "Answer received, containing " << reply->GetSize() << " bytes ";

// wrap incoming bytes as a TMessageWrapper which offers "adoption" of a buffer

auto message = new TMessageWrapper(reply->GetData(), reply->GetSize());

auto chunk = static_cast<o2::data::PrimaryChunk*>(message->ReadObjectAny(message->GetClass()));

mVMCApp->setPrimaries(chunk->mParticles);

auto info = chunk->mSubEventInfo;

mVMCApp->setSubEventInfo(&info);

LOG(INFO) << "Processing " << chunk->mParticles.size() << " primary particles "

<< "for event " << info.eventID << "/" << info.maxEvents << " "

<< "part " << info.part << "/" << info.nparts;

gRandom->SetSeed(chunk->mSubEventInfo.seed);

auto& conf = o2::conf::SimConfig::Instance();

if (strcmp(conf.getMCEngine().c_str(), "TGeant4") == 0) {

mVMC->ProcessEvent();

} else {

// for Geant3 at least calling ProcessEvent is not enough

// as some hooks are not called

mVMC->ProcessRun(1);

}

FairSystemInfo sysinfo;

LOG(INFO) << "TIME-STAMP " << mTimer.RealTime() << "\t";

mTimer.Continue();

LOG(INFO) << "MEM-STAMP " << sysinfo.GetCurrentMemory() / (1024. * 1024) << " "

<< sysinfo.GetMaxMemory() << " MB\n";

delete message;

delete chunk;

} else {

LOG(INFO) << " No answer reveived from server. Return code " << code;

}

} while (code == -1 && trial <= 2);

} else {

LOG(INFO) << " Requesting work from server not possible. Return code " << sendcode;

return false;

}

return true;

}

protected:

/// Overloads the ConditionalRun() method of FairMQDevice

bool ConditionalRun() final

{

return Kernel(fChannels.at("primary-get").at(0), fChannels.at("simdata").at(0));

}

void PostRun() final { LOG(INFO) << "Shutting down "; }

private:

TStopwatch mTimer; //!

o2::steer::O2MCApplication* mVMCApp = nullptr; //!

TVirtualMC* mVMC = nullptr; //!

std::unique_ptr<FairRunSim> mSimRun; //!